Apologia Chemistry: Reaction in a Bag

Tomorrow, we’re finishing the Koolaid activity and doing our first chemistry lab.  Yes, we’ve done labs, but not chemistry labs yet.  It’s one of my favorites: Flinn’s Reaction in a Bag.  This lab requires large plastic bags, baking soda, phenol red, and calcium chloride.  Before you buy calcium chloride on Amazon or eBay, check your garage for Driveway Heat.  Be careful.  There are several versions of driveway salt.  Look on the back for ingredients. The pet safe driveway salt is magnesium chloride, not calcium chloride.  (BTW, Epsom salts are magnesium sulfate.)  Most driveway salt is NaCl or sodium chloride, rock salt.

We are doing this lab according to the instructions.  I’ll post photos.

Apologia Chemistry: Lab Equipment

Update: Check www.shopgoodwill.com for e-science kits.  They have a Physical Science Kit today.  I was at IKEA and saw silicone oven mitts for $3.99.  I use these to handle hot glass beakers or test tubes.  Walmart has silicone oven mitts for $6.99.  (BTW, I used Hot Hands or Hand Heat protectors from Flinn in the classroom.).

Our Chemistry class has completed a few labs this past month.  It occurred to me to mention lab equipment.  A number of web sites sell Chemistry kits for Apologia.  I buy materials for a Co-op class of eight students.  Let me make a few suggestions.  If I were teaching one or two children, I would buy a set of plastic beakers and graduated cylinders.  (This Set has puppets and test tube brushes, too.).  We save and use large yogurt containers, too.  If your experiments involve household chemicals, the plastic containers are fine.   Buy a digital scale and use cupcake paper liners instead of weigh boats.  I’ve purchased eight of these digital scales and have been pleased how well they hold up.  I would buy a scoop for chemicals; we use disposable craft sticks too.  I have ten or twelve scoops on hand.  Buy pipettes for transferring liquids.  (I buy a box of 500 pipettes and use them for two years.). Don’t reuse pipettes.  I do have a few I use with density lab for water.  In general, pipettes are tossed after lab.  We use reaction plates like these.  However, I have used paint pallets as reaction plates at a public school where everything came out of our pockets.  They worked just fine for dilute chemical reactions.  Buy a thermometer.  The inexpensive ones are fine.  Unsure if your thermometer is accurate?  Calibrate it.  We have glass and digital thermometers.  I just gave my set of inexpensive ones to a friend teaching Physical Science.  What about heating materials?  We use electric burners most of the time.  Sometimes, we use tea candles to heat test tubes.  (Dollar Tree sells them, too.). I avoid alcohol burners.  They aren’t safe.  We use flame candles for flames tests.  (Walmart may have sets in the Party section.).  I recommend buying a set of test tubes and a rack.  We do some labs with test tubes.  I would buy a funnel and safety glasses.  You can buy a single pair at Lowe’s or Home Depot.  We use safety glasses because the kids won’t keep the goggles on their faces.  We use our safety glasses all the time for nerf wars.  The inexpensive glasses would make a great party favor for a Nerf War party.

Start at home and assemble a box with craft sticks, q-tips, plastic containers, funnels, perhaps a thermometer.  You may not need a burner.  We do labs in the basement or in the garage and need
burners.  We also use plastic bags, small cups, plastic spoons, coffee filters, cupcake liners, etc. I’ll
try to post photos of the materials as we go.  My point is that some of the materials sold in the   Chemistry kits, such as the burner aren’t safe or useful.  If your budget for lab supplies is $100, you should try to save funds for chemicals.

Apologia Chemistry: Accuracy and Precision and Conversions Module 1

Do you remember when I said that Day One lasts a month?  It did.  Actually, we are still working through Module 1 topics.  What is the difference?  I am adding some rigor.  I spent Week 1 doing graphing calculator exercises---something I might do in the spring.  So where are we now?

I left the calculations for Bowling for Density from yesterday's video on the board for all of the kids to copy.  They have a take-home quiz for Tuesday.  Each child has a different bowling ball weight and must calculate its density.  I made up weights 11.5--14.5. 

Then we did an accuracy and precision lab.  (This is the make-up lab for anyone absent.)  The lab we did uses a sponge, Solo cup, water, and a ruler.  First we defined and differentiated accuracy and precision.  The lab we use has the kids drop a wet sponge into a Solo cup.  We dropped the sponge 30 times.  I have the kids calculate mean, median, and  mode and summarize accuracy and precision.  Then, the kids graph the data in graphing calculators and calculate the one variable stats.  I have them write the calculations in their notebooks and just check they did the calculations correctly, and entered the data correctly.  Basically, it was a quick review of the graphing calculator, too.  (One group of three had three different answers.)

The last thing we did was start the Kool-aid lab.  Each kid gets a different flavor of Koolaid.  They have to do the conversions to make a three ounce cup of Kool-aid.  The units of measure are in grams and milliliters.  They need the conversion from quarts to liters, the number of grams of sugar in a cup, the volume in mL of a 3 ounce cup, and the mass in grams of the Kool-aid on the package.  We'll work on this next week in class.

Apologia Chemistry: Elements and Timelines

I just decided to assign a Timeline to my Chemistry class.  I usually wait and assign timelines for the development of atomic theory and gas laws.  Why wait?  My British Literature kids are creating timelines for each period of literature.  This site has the elements in alphabetical order with the scientist and years of discovery.  I’m going to have the kids add the birth and death for each scientist. Wait.  They must make the timelines on graph paper.  Last year, some of the parents requested moremrigor.  I’m happy to oblige.  I’ll post good examples.

Apologia Chemistry: Bowling for Density follow-up.

Update.  We spent two hours this morning working on Bowling for Density with the two girls.  They made the video below.  No, this wasn't the first take.  It was probably the fourth or fifth take.  Now, both girls can take the Bowling test tomorrow.  Two down and six to go.  We’ll see who understands Bowling for Density.

Surprise, surprise, Bowling for Density is proving to be confusing.  Truthfully, this demo requires higher order thinking.  The question is, “ Will a bowling ball float?”  Maybe.  It depends on the mass of the bowling ball.  If the density of the bowling ball is less than the density of water, it floats.  If the density of the ball is greater, it sinks.  A 12 lb. bowling ball has a density of 0.99.  When it’s placed in a tub of ice water (to get the water density as close as possible to 1.0) it bobbles in the tub.  Thrift stores frequently have used bowling balls.

Tomorrow, two of the girls are going to video Bowling for Density.  I’m going to have them demonstrate how to measure the ball’s mass and volume and show how to do the calculations.  Once the video is completely accurate—including units of measure, I’ll post it my You Tube channel and share it here on the blog.

I’ve done this before with my kids.  They love it!  I think their level of understanding increases.  I’ll be able to check on their level of understanding; I plan to quiz the Chem kids.  The quiz is whether a bowling ball will float.  Each kid will get a different weight ball to calculate.  They must show their work.  I’ll keep you posted.

Apologia Chemistry: Yet More Density and Bowling for Density

BTW, five of the eight students have earned 100 on the 50 elements they need to memorize.  Yes, after taking the test five times, only one more kid learned them all today.  I share your frustrations teaching.  Chemistry is going sloowwwwwlllly.

Today, my husband, Rob, took over Chemistry while I taught some graphing calculator exercises and population pyramid histograms to Stat.  He spent the entire class redoing the density lab--but with calipers and introducing Bowling for Density.  Really.

After class, two of the kids, Lacie and James, spent two more hours with Bowling for Density.  The homework is to determine whether a 10 lb, 12 lb, or 14 lb bowling ball will float.  The density of water is 1.0 g/cm3.  If the bowling ball is less than 1.0 g/cm3, it will float.  If the ball's density is greater than 1.0 g/cm3, it will sink.  Sounds clear.  It isn't.

Bowling balls are 27 inches in circumference.  Their weight ranges from 10 lbs. to 16 lbs.  These are league specifications.  Density is mass/volume.  Since the density of water is 1.0 g/cm3, the mass must be in grams and the volume in cm3.  The volume of a sphere is here.  The first step is convert 27 inches into cm or 68.58 cm.

27 inches = 68.58 cm
 Circumference = 2πr
 68.58 = 2πr
 r = 10.9 cm
V = 4/3πr 3
 V = 4/3π(10.9)3
 V = 5446.8 cm3

Then one must convert lbs into grams:
 453.6 g/lb
10 lb x 453.6 = 4536

Density = mass/volume
4536 g /5446.8 cm3 = 0.83 g/cm3

0.83 g/cm3 is less than the density of water, 1.0 g/cm3.  Therefore, a 10 lb bowling bowl will float.

Here are samples of the work remitted.

The D scribbled at the top is my initial.  It means that I've entered the grade into Classroom.

Apologia: Graphing Calculator

I just read This article about graphing calculators.  In the article, the author mentions
Desmos, a free graphing calculator.  Scroll to the bottom if the home page and click on ‘graphing calculator.’  The format is different from TI 83/84; but, it’s free.  It’s easy to enter data and graph a linear regression.  Moreover, there are lesson on the web site.  

We are going to muddle along with our TI83/84 calculators.  I bought them used; students are likely to encounter TI 83/84 in college.  The other issue with the free or inexpensive emulator, such as GraphNCalc is most cell phones or iPads are not allowed to be used during PSATs, SATs, or AP exams; whereas, the TI 83/84 are permitted.

The author, Zachery Crockett, makes a strong argument—the TI graphing calculators are too expensive—moreover, the calculators are tricky to use.  Creating Stat Plots and graphing regression models are far from intuitive using the TI calculators.  One of my colleagues spent a year teaching himself how to use a graphing calculator for Physics and Calculus before he introduced them to his students.

I’m sticking with TI and helping the kids navigate Stats—which does have TI Calc exercises, complete with screen shots.  But, my husband, Rob, will teach the kids how to use excel, too—both in .Stats and Physics.  Excel will likely prove more useful.  In the mean time, I’m scouring eBay and Goodwill for deals.

Human Biology and Anatomy Physiology...the sequel

The Human Biology class ended Thursday with three tests and a nursing assessment presentation.  Anna wants to go into medicine.  I agreed to continue.  We’ll be using Human Anatomy & Physiology by Marlieb.  Yes, it’s an older edition—much cheaper!  It will serve.  Our plan is to complete a few chapters in Human Biology by Mader and shift to Marlieb.  First, I want to do Urinalysis.  This Thursday, Anna will assemble and test three or four labs.  Then I had a thought.  Before I met and married my husband, I was in the Nursing Program at the University of Delaware.  (I finished three years and could not transfer when he took a job in the Carolinas.  I would have had to retake most of my nursing courses.  I eventually changed majors to Biology with a concentration of Chemistry.  Over my teaching career, I became dual certified in Bio and Chem, and earned National Board Certification in Chemistry.). One of the most difficult topics is Fluids and Electrolytes.

Anna wants more Biology at the cellular level.  After Urinalysis, we are going to tackle Fluid and Electrolytes.  This textbook is more of a self-study program.  It was developed by instructors at U of D. It made the whole topic much easier to understand.  (When I moved to the Carolinas, a friend was struggling with Fluids.  I gave her this book; the nursing program adopted it.)

We are going to try this and see if it helps.  I’ll keep you posted.  Yes, Rob and I are busy.  He has Statistics and Physics; I have Chemistry and British Literature at the same time.  He and I are tutoring Lacie, a freshman, too.  She’s in Chemistry.  Rob is doing Algebra and Guitar.  Lacie is enrolled in Kolbe for her humanities: Literature, Composition and Grammar, Theology, and Latin.  My job is to assign work, check the syllabus, record grades (all subjects—Rob loathes unfamiliar tech.), and evaluate all work.  We haven’t started Composition or Latin.  I’m using Easy Grammar 5 and diagramming until Lacie has a better foundation.  We are busy!

Apologia Human Anatomy or Biology: Speakers

We just concluded the last Human Biology class that ran over the summer.  Wilkie’s mom is a nurse.  She came in and delivered an extensive nursing assessment.  I ran summer science camps for our church; previously, I ran science camps at private schools.  Home-school friends had asked me to lead summer science camps.  Our priest allowed us to run the camps, which followed VBS.  I had enough teen and adult help.  We tried to keep the camp size down to about 40.  The same families came every year.  We had a different theme each summer.  I invited community members to help with the program.  For example, we had a police officer lead a station about mapping a crime scene for CSI camp.  The summer we had Anatomy Academy, we had nurses from our church teach the kids how to take blood pressures and an ambulance.  The EMT toured the kids through the ambulance and taught them how EMTs put people on to stretchers.  He let the kids take turns.   When we had a nature camp, the local forester led the kids through the woods behind the church and taught tree identification.  The church’s Boy Scout troop taught knots.  I scheduled a local wildlife rehabilitation group to bring animal ambassadors.  The kids loved the skunk. An environmentalist taught the kids how to collect and test pond water.  (That summer camp, I had a different guest every day.)   I paid $250 for the wildlife group.  Otherwise, local leaders were volunteers.  The forester, environmentalist,  police officer, and EMT, often volunteer to promote community relations.

If you are teaching Human Anatomy, consider your local resources.  In our area, there is a rescue station that host Scout troops.  I know the kids could learn more about EMTs.  I would think about teaching the kids CPR and First Aid.  

When I looked for help or speakers, I started with my church.  I did teach locally; I sponsored a large environmental club.  I wrote a number of grants and partnered with several agencies.  So, the Nature camp was a cinch.  Forestry, Trouts Unlimited and Soil and Water Conservation agencies often have education specialists.  Typically, they can bring Enviroscapes and ground water models to demonstrate.  Water specialists can teach how to identify macroinvertebrates and how to test water.  They have the supplies.  Start with the Soil and Water Conservation education specialist.  They usually have a number of local contacts.  Just call and explain that you would like to plan a field trip to the creek.  Ask what models they have.  Many have a watershed model from Enviroscape.  Ask the educator for help.  Tell her about your Co-op group, their ages, topics of interest, and ask what materials she has to share.  Really!  Outreach is her job.

Apologia Technology

I’m trying to post a bit more often while I have time.  Yes, I’m back on my hobby horse!  Use technology!  I was the only Chemistry teacher at small private schools.  I was concerned that the kids would be short changed if they did not get exposure to tech.  I have the same concerns for my home-school Co-op kids.

How do I address these concerns?  We use graphing calculators.  We also use Pasco Spark, Airlink, and Sparklink with a variety of sensors or probe-ware.  My husband, Rob, used the Spark and motion sensor to do the Are You Speeding? lab in Physics.  The Airlink and Sparklink pair with an iPad.  I had to download the Sparkvue app and labs.

I just bought a second Spark interface because they come pre-loaded with the basic labs for elementary, middle, and high school sciences.  The iPad Sparkvue app requires the most recent iPad version.  Another advantage of the Spark interface is the complete lesson.  The lab, Are You Speeding?, has instructions, an activity, and review questions.  I like to let the kids play with the motion detector running in place, walking, standing, etc.  The Chemistry kids will use the Spark to do a lesson with water.  My kids use the interface as a digital thermometer or ion conductor.  Pasco has older technology such as the GLX data interface, also called Xplorer GLX.  These devices connect to a probe and display data.  The GLX is exceptionally rugged.  The Pasco sensors can be used with the GLX, Spark, Sparklink, or Airlink.

The TI 84 can also be used as a digital thermometer with Vernier’s Easy Temp thermometer.  The micro USB connector is at the top of the TI 84 graphing calculator.  The calculator is preloaded with Easy Data software.  As soon as you plug in the thermometer, the software opens on the calculator and reports the data in degrees Celsius.  The data is stored in the STAT function on the calculator.

Vernier sells Go! Temperature probe  which connects to a laptop via a USB connector.  Vernier has a Go! link which allows kids to connect other Vernier probes.  Yes, I buy most of my sensors or probes on eBay.  Really.

Apologia Chemistry: It’s All About Density Wrap-up. Finally.

Flinn Scientific has some of the best material, kits, and activities for Chemistry.  I ordered the density kit initially for my Conceptual Chemistry classes in public school.  (Most of the college bound students in both private and public school have mastered density.). (It’s All About Density is the student hand-out.  Here are the teacher notes.).

Instead of using the kit, I take out several objects: marbles, cylinders, and cubes.  I want the kids to compare measuring volume by displacement in water with measuring volume by geometry.  The kids wrote a hypothesis speculating which volume method was more accurate.  One kid, Ian, said the null hypothesis; the two are equally accurate.  The kids must create a data table with three objects: a sphere, a cylinder, and a cube.  In the data are the respective masses, volume by displacement, volume by geometry, density, accepted values, and percent error.  Lastly, the students must write whether the data supported or refuted their hypotheses.

I’ll post a good example of the lab report next week.  One child did finish; I returned it to him without taking a photo.

The only issue was the displacement volumes were more accurate than geometry volumes.  Lacie missed class.  She was confused anyway.  I found calipers; she will redo the lab with calipers next week.

Human Biology or Anatomy: Electrolytes and Ions.

Anna and I are plodding onward through Physiology.  I want to add more labs.  Both Physiology and Chemistry employ Conductivity labs with conductivity meters.  In Anatomy, the lab is called Electrolytes and Ions.  I’m going to have Anna make the solutions and conductivity meters to prepare and test this lab.  I’ll let her select the lab format she prefers.  Why?  We did not talk about Nutrition during the Digestive unit for Human Biology.  Electrolytes are important for nerve and muscle functions.  The Physiology course has loads of detail.  My plan is to assign reading selections, more coloring pages, and labs to both do and test.  We are playing this by ear.  The conductivity lab will be very handy for Chemistry.

Human Biology or Anatomy: Urinalysis

One common anatomy lab is Urinalysis.  When I was an undergrad, the students were instructed to avoid caffeine for 48 hours before the Urinalysis Anatomy lab and test one’s own urine.  I remember I forgot and produced liters of light fluid.  Anatomy classes tend to use simulated urine to test.  Home Science Tools offers a kit.  If you have a Co-op class, it makes sense to invest in a kit.  Anna and I are going to work alone.  I think I’ll have her prepare a diy urinalysis kit.  I have Benedict’s solution and Biuret reagent to use.  (This Safety Data Sheet from Flinn for simulated urine has some of the ingredients.  This urine lab developed by Siemens for STEM day has some good ideas for lab.  Flinn also has suggestions for teachers to create a urinalysis lab.  

This kidney filtration simulation dovetails well with urinalysis.  Home Science Tools has a kidney and blood filtration kit available.  

There is nothing wrong with buying kits.  When I taught in private and public schools, I had a budget for lab supplies.  Frequently, I ordered a kit to evaluate the contents and decide if the materials might be cheaper to assemble myself.  Some kits, such as Flinn’s stoichiometry lab kit, I ordered every year for my chemistry classes.  The price of the kit was about the same as the individual chemicals; I did that lab every year.

My plan is to have Anna test and assemble a kidney filtration and urinalysis lab herself.  She has two younger brothers to teach.  Your understanding is much greater if you teach the material.

Human Biology: Wrap up and Nursing Assessment

Today concludes Human Biology.  I wanted a nurse to come because Anna is considering nursing or some form of medicine. She wants to continue with Physiology and Anatomy.  We’ll finish Human Biology and begin Anatomy and Physiology.  Today we had three labeling quizzes: Respiratory, Muscles, and Skeleton. 

After the quizzes, Wilkie's mom, Mrs. Cook, did a complete nursing assessment from head to toe.  We’ve had relatively few labs this past summer.  It was outstanding!  Mrs. Cook worked as a cardiac nurse for 14 years and currently works on a maternity ward.  She is up to date!  Mrs. Cook went over in detail a head to toe physical assessment using two of the boys as patients.  (We had to switch patients when Zach got too ticklish.)  She spent an 1 1/2 hours doing demonstrations: how to palpate, take vital signs, percuss a vein, etc.  Mrs. Cook prepared detailed notes and brought her flashlight, stethoscope, B.P. cuff, etc.  She brought a straw and cups to demonstrate 'crackling' in the lungs.  I took ten pages of notes.  It was such an excellent way to conclude class.  If you teach Human Anatomy or Human Biology, consider asking a nurse to demonstrate a complete nursing assessment.

Apologia Chemistry: Density Lab

Update: The kids have finished the density lab.  Finally.  Actually, they still need to finish their lab report.  The report must have a title, a data table with a sheer, cylinder, and cube.  Each object must have both volume by displacement and volume by geometry calculations, densities with units, and percent error.  Finally, the report must have their hypotheses, a description method was more accurate, and whether the data supported or refuted their data.  The kids found volume by displacement is more accurate.  Volume by geometry should be more accurate.  If we used calipers, their finding may be different.  Ian hypothesized the null hypothesis, both methods are equally accurate, or in this case inaccurate.  One kid, Lacie was absent.  I’m going to dig up the calipers and have her redo three objects next week.

Last week, the kids started a Density Lab.  Last week, the kids began the density lab by weighing several objects.  I’m sure they lost the data.  The first Chemistry labs try one’s patience.  I review how to weigh with a digital  scale and how to read volume with a graduated cylinder. I have to review   the formulas for density and volume of several geometric shapes.  Kids do not listen.  They need to use a weigh boat.  This lab has solid, household items.  When they weigh chemicals, they need to always use a weigh boat.  I use this digital scale.  I came across these scales in an escience kit I got from Good Will online.

In any case, the class must select at least six objects and be able to calculate the volume three objects both by displacement and by geometry to compare which method is more accurate or has the least error when compared to the accepted value.

Today, we finished another periodic table test and worked on the density lab.  Yes, that’s all we did.

Apologia Chemistry Module 1: Metrics and Significant Figures

Two topics in Module 1 are metric conversions and significant figures.  One mnemonic for metric conversions is Many (Mega ) Kids (Kilo ) Have (Hecto) Dropped (Deka) Over (base unit) Dead (Deci) Converting (Centi) Metrics (Milli).  This metric conversion worksheet has most of the mnemonic—all but Mega.  Kids struggle with metrics.  (Here is another metric table,). What is the answer?  Practice.  The Cavalcade of Chemistry has loads of practice—many with answers to check your work.  Does your child need more of a challenge?  This worksheet has conversions, significant figures, and scientific notation—with an answer key!  Here is a scientific notations worksheet.  Here is a significant figures worksheet.  This is the last one.  It has all three: significant figures, conversions, and scientific notation.  Can you hear the screams?

Apologia Chemistry: Nomenclature or Ionic Compounds in Module 3

Yes, I'm getting ahead of myself.  Every year, I use this activity, Putting the Ions in Their Hands with my students.  I've used it for classes ranging from eighth grade physical science to college chemistry.  Make print copies of the two data sheets.  Print the Ion Formula Chart on card stock in a bright color.  Then print the cations on to card stock in a different color.  (Mine are red.)  Finally, print the anions on to card stock in a third color. (Mine are blue.) (No, I’m not color blind.  When I made the sets below, I used the card stock I had on hand.)  Cut out the ions before class.  I made several sets for my Co-op class.  I draw the first sample ionic compound, aluminum chloride on the white board with red and blue dry erase markers.  The kids make up the ionic compounds with the cards and write the formulas.  I work with kids on the tricky ones.  Lastly, I have them make up three or four different ionic compounds on their own.  I'll post photos when the kids make their compounds.

It sounds like a lot of work to make the copies, buy card stock, etc.  (eBay sells small lots of card stock.  It’s more costly per sheet; however, if you don’t use card stock often, a small lot makes more sense.)   Below is a set of the nomenclature cards.  I copied the cations, anions, and ion chart on to card stock with an ink-jet printer.  Use two colors of card stock: one for the cations and one for the anions.  The original kit from Flinn Scientific has red for the cations and blue for the anions.  I like to print the ion chart on to card stock, too.  It's easier for the kids to locate when they have a bunch of tables, copies, etc. on their tables or desks.

Apologia Chemistry: Why are you teaching the Periodic Table and nomenclature now?

As soon as my kids complete the topics in Module 1, we are going to start learning ionic and covalent  formulas which are located in Modules 3 and 5 of Apologia Chemistry.  We will do Module 2 in the spring right before Gas Laws.

In fact, my kids are memorizing 50 key elements in the Periodic Table; they made element cards as a summer assignment before class began.  I’m testing them each day at the beginning of class several times.  Why?  One reason is parents and students associate the Periodic Table with learning Chemistry.  The other reason is that kids need to know the names of the elements before they can name and write formulas, identify types of reactions, and balance equations.  So, I do these topics sequentially.  I also alternate qualitative topics such as periodic trends, atomic theory etc. with quantitative material such as moles and Stoichiometry.

So, as soon as the kids have memorized the key elements, reviewed all of the math topics in Module 1, we are launching into Module 3 ionic formula nomenclature and a lab introducing chemical reactions.  I’ll keep you posted.

Apologia Chemistry: Module 1 Are you following the textbook?

Do I follow the Apologia Chemistry textbook?  A little.  I started much of the content from Module 1, but not in the order presented in the book.  Friday, I jumped to Module 1 derived units and plunged right into Flinn’s It’s All About Density Lab.  I want to demonstrate a few lab skills, such as using a weigh boat, how to zero a digital scale, and how to read volume below the meniscus with a graduated cylinder.  Doing this density lab allows me to introduce present error and talk about significant digits, and the limits of our equipment.  The kids will review metric measures and work on metric conversions in the next week or two.  I like the kids to do the Koolaid lab and Accuracy and Precision lab first.  I’m a big believer in lab first, lesson second, and practice last.  Often the lesson comes with the lab.

I also substitute labs for experiments in Apologia Chemistry.  For example, Dr. Wile’s Experiment 1.4  is the preparation of a density column.  There is nothing wrong with this experiment.  I’ve had kids set up Density columns as demos.  I’m a big fan of inquiry labs.  When my kids do the Flinn Density Lab, I have them hypothesize which method, volume by displacement or volume by geometry is more accurate?  How will you determine which method is more accurate?  Did your findings in lab support or refute your hypothesis?

Yes, I’m doing topics in Apologia Chemistry.  Often, Dr. Wile’s explanations help kids make sense of Chemistry.  I’ve taught Chemistry for over 25 years and have accumulated loads of ideas for labs and activities.  So, do we us the textbook?  A little.

Apologia Chemistry: Safety, Quizzes, Density

Quick Update: My husband and I are switching at the beginning of class.  Rob is monitoring the quiz while I review different functions on the graphing calculator with the Stat kids.  He and I are going to switch off and on--probably once a week initially.  My kids are learning the elements: his kids are learning how to enter data and produce different graphs.  Both exercises take about 15 minutes.

Today, we had a Periodic Table test with 50 elements, an equipment quiz, a safety quiz, and began It’s all about Density.  The kids had time to weigh a bunch of objects at the end of class.  The lab takes about 45 minutes.  Below are photos of the materials used.  The small cubes are similar to these density cubes from American Science and Surplus.  Most of the objects are marbles, a cork from a wine bottle, etc.  The yarn is to measure the circumference of the glass spheres.  Some of the objects are irregular and volume must be measured by displacement.  The cork floats and volume must be measured by geometry.  The kids are going to learn which method, volume by displacement or volume by geometry is more accurate.  I'll introduce percent error, too.

Apologia Science--We are home!

Update.  One issue we have using our basement is lighting.  The first week, all 16 Stats and Chem kids were crammed together learning how to use the graphing calculators.  We bought a garage overhead light with LEDs.  It is bright.  Will it last?  I bought one with a two year warranty from Amazon.  We shall see if it lasts.  For now, it is much safer for the Chem kids to do lab.  The next step is to have them wear shoes during lab.

This year, my husband, Rob, and I are much more organized!  He is teaching Statistics and Physics for the Co-op.  I'm teaching Chemistry for the Co-op, finishing an elective Human Biology class, doing all of the home-schooling for Lacie, and working through British Literature with two upper class girls.   But, this year, we are in our own basement.  We don't have huge bins, rolls of plastic table covers, and boxes of books and notes.  Yeah!  All of our equipment, tables, chairs, white boards are in our house!!!!!!  We have a copier, LCD projector, wi-fi, pencil sharpener, lab supplies, chemicals, equipment on shelves or tables in the basement.  That means we can organize everything in advance.

In reality, it means 50 trips up and down to the basement.  But, I can sort my quizzes, lab equipment, demos in advance, much as I did when I taught in public and private schools.  In reality, I help my husband organize his labs and notes, and locate all of the lab equipment for Physics, too.  Arrrgggghh.  Evidently, locating objects is an X-linked genetic trait.

Five years ago, I taught Chemistry and Physical Science concurrently at my house.  The students were every where.  The Chemistry kids did their labs in the garage (with heaters during the winter.)  The Physical Science kids did most of their labs upstairs in my kitchen.  I worked upstairs in my dining room with the Chemistry class while a mom supervised the Physical Science kids downstairs in the den or sometimes upstairs in the living room.  We managed.


This year, we'll all be in the basement.  Yes, it is pretty big.  Finished basements in our neighborhood are about 750-1000 square feet in size--enough for a den, bathroom, laundry room, and bedroom.  We have rugs and a fan on my husband's side to minimize noise from the Chemistry class.  I am loud.  The kids are pretty good.  We all are learning how to keep our voices down.  It's like open classrooms in a public school.  Not ideal.

Tomorrow, we're having two more quizzes.  So far, a little background noise from Statistics doesn't bother the Chemistry class when they test.  Rob says he cannot hear the kids--but he can hear me.  Yet another work in progress.

Apologia Chemistry: Density

After the Periodic Table test and the equipment test tomorrow, my plan is to do two labs: Accuracy and Precision Lab and Flinn's Density Lab.  I am comfortable using this data shee t because I've purchased more than six of these kits.  This is an alternate lab using the two methods: volume by displacement and volume by geometry. 

The lab kit sold by Flinn has the objects described in the data sheet above.  We use metal cubes, wood blocks, marbles, cylinders, etc.  Not all of the objects fit into a graduated cylinder and the volume must be determined by direct measurement using geometry.  I ask the kids to hypothesize which method, displacement or geometry, is more accurate.  They compare their answers with known values, using a table with accepted values for common objects.  Be sure to have a small cylinder of water--say 10 mL.  The kids can weigh the water and measure the volume in the cylinder to determine the volume. 

This is an opportunity to introduce percent error calculations and crying...

I plan to use an alternate lab for accuracy and precision.  For this lab, the kids use a plastic cup, ruler or meter stick, and a sponge.  The kids wet the sponges and drop it one meter to hit the cup.  If they miss the cup, they need to measure the distance the sponge landed from the cup.  The kids collect 30 data points and calculate the mean, median, and mode.  It's a good way to introduce experimental design and review simple statistics.  I'm pretty sure, we have enough material here for tomorrow.

Apologia Chemistry: Periodic Table Test Tomorrow!

The Chemistry class all completed their summer assignment and made about 40 elemental cards.  The summer assignment included main group elements--not transitional metals or Transition elements. The kids are using their cards to study but must learn common elements, such as iron, copper, silver, and gold, too.  The two girls (the only girls) are using quizlet (Periodic Table of Elements) and The Elements Song to learn the names.  Warning!  The Elements Song is a terrible ear worm.

Human Biology: Respiration Labs

Today, one of the moms, a nurse, was going to instruct the kids by doing a nursing assessment.  She fell ill; we did two other labs.  The first is with BTB and CO2.  The kids fill a beaker with 150 mL of tap water, add 45 drops of bromothymol blue (BTB), and blow through a straw into the water until the solution changes from blue to yellow.  The lab cited above quantifies the exercise.  Instead, we did the demo and talked about pH, pH indicators, and how CO2 and water form carbonic acid.

Our time was spent designing and performing a Tidal Volume lab.  The kids did use milk jugs, buckets, and plastic, aquarium tubing for the lab.  We used large, plastic 1000 mL plastic beakers to measure the water instead of 100 mL graduated cylinders, which are more accurate.  The milk jug, bucket, and beaker are all crude measures.  The kids filled the milk jug with cold tap water and closed the lid under water to remove as much air as possible.  They inverted the closed milk jug into the bucket filled with about 4 L of water.  After the jug is under water, the student removes the lid and inserts the tubing, and takes a deep breath.  The air displaces some of the water in the jug.  Once the kids measure the amount of water remaining in the jug, they refill the milk jug and pour it out to measure the original amount of water.  It's not a gallon.  One gallon of milk or 3.87 L is the volume of milk in the container--not the capacity of the jug, which is 3.9 L.  The kids need to subtract the volume of water after they breathe into the jug from the original amount in the jug.

We spent 45 minutes reviewing the lab rubric.  The purpose of the lab is to understand tidal volume.  The lab should be written in complete sentences and include a data table.  The results from the lab (tidal volume data from all four students) must be reported with the statistics: mean, median, and mode.  The report should include both a discussion (source of errors) and conclusion.  We have NOT down a formal report in Human Biology since spring.  All of the kids have had to do these types of reports in Biology, Chemistry, and Physics.  I'll post samples once they are graded and edited.  My students may rewrite their reports until I'm satisfied or they have a fit--whichever comes first.

Apologia Physical Science: Sound. Palm Pipes

I’m teaching Chemistry.  My husband, Rob, teaches Physics.  I’m always looking on www.shopgoodwill.com’s website for interesting science equipment.  Recently, Goodwill listed Palm Pipes.  When I researched how they work, I came across Palm Pipes, an Exploratorium Activity.  The activity uses PVC pipes and a good explanation of the science.  Fun, right?

Statistics Class

Update: The kids finished both the M&M lab part 2 and Water Water.

M&M lab:
Each student used 25 grams of M&M's.  Each student counted the M&M's by color and compared the results, as percent of total sample, to the color mix percentages published by Mars Candy.  We then calculated the percent error.  All M&M's were counted at one time, demonstrating counting without replacement.
We then counted by color each sample by pulling one M&M at a time and putting it back into the sample before pulling the next M&M.  The sample was shaken before each count.  This demonstrates counting with replacement.  The results were different from the first count for some color counts but the same for others.  Sampling with replacement is used for example in counting wildlife.
The students reached conclusions concerning the importance of sample size and counting method.

Water water lab:
The purpose of this lab was to determine if the students could taste the difference between bottled water and tap water.  I gave each student four samples to drink and compare:  two samples with tap water and two samples with bottled water (two different brands of bottled water).  I asked each student to determine which samples were bottled and which were tap water.  Each student also picked the best tasting water.  I asked to students to think about which variables were controlled: common cup, water samples at same temperature.  Uncontrolled variables included students' taste buds (accuracy, impacted by drinking soda, smoking, etc.), whether the student was hungry or thirsty.

Results: three of six students picked correctly the two bottled water samples.  The other three were half correct.  Four students picked as their favorite water one of the bottled samples however two of these students picked the cheaper bottled water as best tasting.

This lead to an Economics lesson: how much is it worth to drink bottled water if only half the class could clearly differentiate the taste?

My husband, Rob, is teaching Statistics using this edition of The Practice of Statistics.  (We are using this edition of The Practice of Statistics for AP, too.). Incidentally, he hates to blog.  I’m going to have his post updates to his physics blog for the sake of the kids who need to have a record for their portfolios.  Basically, we are planning and selecting the material together.

We selected the older edition because it’s cheaper.  We’ll update data sets as we go.  Rob is doing the teaching; this is the only time I’ve ever seen him uncertain about instruction.  Stats are more descriptive, require graphing calculators, and experimental design.  So, he and I are planning the class together,

Last week, Rob and I taught the kids how to graph with a graphing calculator.  Tuesday, Rob is on his own—four of the eight kids in his class seem to be proficient with the graphing calculators.  Tuesday, he’s posting a set of data and quizzing the kids to see if they can graph.  After the quiz, he’s giving the kids a reference sheet for TI84.  (The TI 83/84 are very similar to use.). 

Next, Rob is going to finish the M&M lab.  He plans to have the kids calculate percent error between their individual results, the class results, and the percentage by color in milk chocolate M&Ms.  Last week, the kids were getting too involved with these calculations.  I had to remind them we weren’t curing cancer—just doing an exercise to learn how to create a histogram.

There are enough candies remaining, Rob is going to have the Stat class take 25g samples and record results (30 trials) of removing candies with and without replacement, to determine which approach is best to determine the color composition of M&Ms.  

I think this will take an hour.  If not, Rob is going to do the ‘Water, Water’ exercise in Chapter 1 of the Stat textbook, to teach the kids about hypotheses and experimental design.  

We are also leaning hard on Mrs. Daniel’s AP Statistics Class blog for ideas.  Stay tuned.

Apologia Chemistry: Day One Activities

Update: We took a graphing calculator quiz, the math pre-assessment, a Periodic Table quiz, and an introduction to the names of equipment.  Wooooo!  It just takes time to go over all of the answers.  For the graphing calculator quiz, I posted data and instructed them to put the data into L1 and L2, graph the data, and calculate the regression.  Yeah!  With a little help, all of the kids could do it.

I’ve taught Chemistry for over 20 years.  So, I have a few ideas about how to begin the class.  I’m open to new ideas; there are some activities that work year after year.  The intro activities are all lumped into a category called Day One.  This year, we began with graphing and experimental design. Now, we’re starting Chemistry.

Day One includes a Math assessment,  Safety Contracts, a safety quiz, measures, the names of chemical equipment, Accuracy and Precision Lab, It’s All About Density Lab, and The Koolaid Lab.

Day One can last two weeks.  This week, I want to do some assessment.  First, I plan to see if the kids can graph a set of data with the graphing calculator, calculate the equation of the line, and produce a regression.  Next, the kids made Periodic Table Cards as a summer assignment.  I’m going to give them  Periodic tables with symbols only to see how many elements they learned by making the cards.  I need to go over the names of common lab equipment.  After, I’ll review, do a practice quiz, and finally test them on the equipment.  As an aside, I let kids retake any quiz or test.  In fact, I retest some material until they achieve mastery, usually 85% or better.  Because we use the elements so often, I need 90% mastery on about 60 elements.  I doubt I’ll finish everything this week.  I will keep you posted.


Sorry for not posting photos last week.  I was so involved teaching 16 kids how to graph with a TI83/84, I forgot to take photos.  I took a few today as the kids were taking their graphing calculator quiz.

Apologia Chemistry: Graphing Calculator Lesson 2

Update!  Yes, we finished the M&M lab, graphed the data in a histogram and practiced several data sets!   Whooooo!  This seldom happens!  We finished the planned lessons.


The Chemistry class meets Tuesdays and Fridays this year.  Tomorrow, my husband, Rob, and I are doing another combined Chemistry and Statistics class to introduce experimental design and how to use the graphing calculator.  

First, we're using this graphing exercise to see if the kids can enter the data into the STAT function, turn on STAT PLOT, set the range, graph the data (depth and average temperature), calculate the linear regression, and overlay the line of best fit over the scatter plot data.  In other words, see if they remember our lesson from Tuesday.  Maybe.

Next, Rob and I are going to do this Statistics and Probability Lab with M&Ms.  He and I have 15 small cups of 50 gram samples of the candies, from a party-size bag of regular M&Ms.  Most of the M&M labs use individual bags of candies for each student.  The party-size bag was cheaper; so we weighed 50 g. samples before class.  

We decided to have a quick discussion about experimental design, hypothesis, and controlled variables before the lab.  Basically, the kids are going to predict which color M&M candy is the greatest percent in the candy sample (alternate hypothesis) or the percentages of each color are the same (null hypothesis).  This article explains how two companies produce M&Ms varies slightly by company. The percentages by color are in this article--for milk chocolate candies!  

We are going to give each child a cup with 50 grams of candies.  They will count the number of each color candy and calculate the percentage of each color in the cup.  Next each table of three kids will pool the data.  Finally, we'll pool and calculate the class data.  Next Tuesday, Rob is going to do two other exercises with the Statistics class, such as sampling with replacement and outliers.  Once we have the class data, the kids are going to graph it in the graphing calculators and produce histograms--bar graphs by color.  Yeah!  

What does this have to do with Chemistry?  Very little.  However, it will allow a brief discussion of experimental design and introduce the kids to the graphing calculator.