WA and Apologia Science: CER

CER is claim-evidence-reasoning.  This process requires kids to make a claim, support the claim with evidence or data, and explain their reasoning or thinking.  Edutopia has an introduction to CER.  Next, you will want some examples and a slideshow.  When I introduce kids to the idea of CER, I use Slide 19 in the slideshow just linked.  I broadcast the data table and ask kids if all the liquids are the same.  They study and table and say whether or not the liquids are the same.  The key is to lead the discussion to get the class to articulate their reasoning based on the evidence posted in the table.  Get in the habit of asking kids to support their claims with data.

Apologia Chemistry Module Eleven Solubility

The Apologia chemistry textbook, Experiment 11.2, The Effect of Temperature on the Solubility of a Gas gave me an idea for an inquiry-based lab.  Last fall, a fifth grader at WA, Julia, wanted to test her hypothesis that hot soda goes flat faster than cold soda.  I was helping the fourth and fifth graders understand the science fair process.  When Julia explained her idea, it occurred to me that I had a CO2 sensor, part of a set, a Pasco rep. had given me after a conference which I had never used.  Ever. Julia and I were able to trouble shoot the apparatus.  Now, that I have learned the quirks of my Sparklink interface, I have lost most of my inhibitions about tackling new sensors.  Here are some screen shots and a photo.

In any case, Experiment 11.2 can be adapted to an inquiry based lab, using CER, claim based evidence.  In other words, we used Julia's science fair project to examine gas solubility in solution.  My Chemistry kids spent some time discussing gas solubility with a coke can as a prop.  Once the kids could articulate that carbon dioxide gas would fizz faster from a warm can of soda than an ice cold can, they were ready to start.  I demonstrated the CO2 sensor, took it completely apart and made them reassemble it and connect the iPad with its app to the Sparklink.  Then they brainstormed ideas. I made a few suggestions, such as using the same container for the bath and creating a room temperature water bath instead of testing one outside of a water bath.  When they asked what room temperature was, I pointed to the temperature probe collecting data.  I also had to ask them how long would they collect data and how long would they allow their cans of soda to equilibrate.  Once completed, the kids wrote a formal lab report.  They are finishing these for homework. Before, during, and after the lab, I asked the kids a few questions: What is the purpose?  What are potential sources of error?  How does gas solubility change with temperature?  The kids should answer these in their labs.  Just as a review, for me a standard lab report has a title, purpose, materials, procedures, data, discussion, and conclusion.  A standard conclusion is that more trials are indicated.

This lab provides an opportunity for CER, claim-evidence-reasoning.  This CER example provides a model.  For this experiment, the claim is that gas is least soluble in very hot water and most soluble in a solution which is very cold.  The dissolved oxygen concentrations are highest on a cold winter day. The evidence for this claim is that a can of soda in very hot water produces more CO2 than a can of soda in ice water.  The reasoning has to do with the gas solubility in solution or more gas remains dissolved in solution in icy water than in boiling water.   CER requires logic and critical thinking.  Kids hate this process.  It's hard work.  I love CER.  Here is a process to get kids to think through a project and articulate their findings.

WA and Apologia Physical Science Electricity

Both of my Physical Science classes are doing the same lesson on Electricity with the same labs and activities.  I also teach Chemistry, Earth Science, and Life Science at a Co-op and a small, private school.  It was a little nuts!  So, to save my sanity, at least one subject is on the same page.  The time-lines and concept maps are in various stages of completion in both sections.  This is completely normal.  Kids are absent; some just take longer to do written work.  These two assignments are being completed on an electronic device.  (Two groups asked to create their time-lines on graph paper.  They did not want to invest the extra time to research how to create a time-line in Excel.  Fine.)

We did three activities for static electricity with sticky tape, balloons, and an aluminum pie plate.  The first activity is with sticky tape statics.  This involves three pieces of tape.  Stick two to a kids shirt.  Remove the tape and hold the two pieces slightly apart; they repel.  Take a fresh piece and hold it to one of these pieces of tape.  All I want to reinforce is that like repel and opposite attract.  Static Charge on a Piece of Scotch Tape describes the underlying science.  Knock yourself out!  I ask the kids to tell me what static electricity is. Be sure to ask the big questions.

This week I wanted the kids to play with  Squishy Circuits.  That lasted five minutes.  Once they were able to light an LED bulb, they were done.  I know better!  The kids need a specific challenge!  Here are photos of the kids at work.  What did I do differently?  I gave them a specific task.  I had made copies of Circuits and the Flow of Electricity Lesson .  I made sure they could differentiate between a series and parallel circuit and then told them they could use any of the materials in the box to make both types of circuits.  Then I let them loose.  My box contains several types of bulbs and batteries, electric tape, clothes pins, alligator clips, paper clips, brass brads, etc.  the kids also had the conductive clay from the squishy circuits.  Then the kids went to work.  I only interrupted long enough to take a few pictures because it my interference can block this sort of productive activity.  The moral is to be sure to give kids a specific task, one which is not too open-ended.

Apologia Chemistry: Acids and Bases

Our Co-op had an extra class to make up some ground.  This past winter was brutal.  The kids did a serial dilution with dilute HCl and NaOH.  The students set up two sets of test tubes, each containing 9 mL of water.  We prepared two solutions: 0.1 M HCl and 0.1 M NaOH.  The kids remove 1 mL of th0.1 M solution and add it to the first test tube, stir, and remove 1 mL from the next and so forth.  After the dilutions, they add half strips of wide range pH paper.  The idea of doing a serial dilution with pH paper is for the kids to see the correlation between pH and concentration.  Well, they don't.  I had them record their data in this manner, drawing test tubes with the dilutions and pH.  Afterwards, I showed them how to calculate pH using a calculator, they seemed to see the relationship.

I think it is good for kids to prep solutions.  I make a point to show them how to label the secondary containers with the formula, molarity, date, and initials.  I walked the kids through the process of using M1V1 = M2V2 for both dilutions and titrations.  As the kids did their Titrations, they noted that something was wrong with the acid concentrations.  The stock solution of HCl indicated that the
concentration was between 32% and 36% or 10.17 M and 12M.  I prepared the acid solutions because the stock solution is so concentrated.  I ended up making 0.1 M solutions twice, once assuming 36% and a second time using 32%.  The kids repeated the titrations.  The acid was not at full strength.  Not quite the lesson I planned to instruct.  I wanted them to understand the process of titration with phenolthalein, HCl, and NaOH.  They used logic to deduce the acid strength was off.  Sigh. At least they got a number of titration trials.

Apologia Physical Science: Suishy Circuits

The Physical Science class began Electricity on Wednesday; our class had an extra lesson this week owing to the number of snow days this past winter.  In an earlier post, I mentioned that the kids are working on concept maps and time-lines.  This morning they made the play dough for Squishy Circuits.  We have had mixed results getting the bulb to light.  One student, L. reminded me she had tried this earlier for her Science Fair project and gave up in frustration.  Last summer, the squishy circuits didn't work either.  But, one group from my high school class had gotten them to work once; but, it did involve a great deal of profanity and numerous trials.

Today, L. and O. decided they would rather finish their time-line of scientists than experience the frustration of squishy circuits.  But guess what? P. got it to work!!!  A nine volt battery will blow the bulb and two AA batteries are not enough.  P. used four AA batteries and reduced the amount of conductive clay.  Here is proof!

WA Life Science: Dissections II

My Life Science class is comparing different animal phyla.  My approach is pretty traditional.  The class is using MRS GREN in a chart to compare representative animals in nine major animal phyla.  The kids just started to dissect.  I ordered animal survey sets: earthworm, clam, starfish, crayfish, oerch, and frog.  I posted some resources for dissections in an earlier post; it won't hurt to assemble some resources again.  I keep loads of references out as the kids dissect, including photos of dissections.

I believe in dissection packets, especially those that make the kids examine their specimens more closely.  The Biology Corner has dissection guides and links to virtual labs.  Virtual dissections can be useful, if funds are tight or for a child home-bound for illness or a family crisis.  Home-schoolers may elect to supplement a few selected dissections, such as the earthworm and frog with virtual dissection labs to stretch their school budget, especially large families.  I am old-school and believe kids need to dissect.

Here are the packets we are using: Earthworm, Clam, and Starfish.  This Imgur album has some photos of my kids dissecting and a copy of the MRS GREN chart they are completing to compare nine major animal phyla.

WA Life Science: Dissections

Finalky the kids started a series of dissections.  Earthworm Dissection Packet is similar to the packets the kids are completing as they work through the survey of animals.  This process is part of comparative morphology, examining different traits or characteristics of animals both simple and complex.  Check out this example of the earthworm specimen.

Apologia Science: Technology and Probeware or Sensors

Technology!  Again?  I know, I know!  Your Co-op should not be intimidated by Pasco or Vernier probes or sensors.  Cost is also not a barrier.  Some of the older technology is fine.   eBay often sell Pasco's GLX Interfaces and sensors.  The GLX pictured predates AirLink and SparkLink interfaces.  Most of the Pasco sensors are compatible with the different interfaces.  While I have never found any of these devices to be intuitive, my students do!  I hand them a device, show how to turn it on, and explain that if they get stuck to hit the little house icon for 'home'.  GLX Labs are widely available on the web.  There are plenty of resources and the Xplorer GLX is very sturdy.  Take a look at the ease of operation.

Apologia Chemistry: More Titrations

There are apps and virtual titration labs and the Utitrate app is free.  The problem for a neophyte is that too often the whole titration concept is foreign.  So an app or virtual lab isn't necessarily going to help.  Scientists use Titrations to determine the concentrations of unknown substances.  Many test kits are back Titrations.  The idea is to neutralize an unknown concentration of a solution with a known concentration.

Apologia Chemistry: Acids and Bases

Acids and bases are familiar chemical compounds and students enjoy these experiments.  Our Co-op is going to do acid-base titrations using microscale techniques.  Typically, titrations involve liters of acids and bases and an expensive buret.  Microscale uses small, dilute volumes of acids and bases, making this safer and practical for Co-ops or schools on a tight budget.  Microscale Acid Base Titration is a good example of the type of titration ordinarily performed in a chemistry class.

Vernier's Microscale Acid Base Titration lab works well if your class has a pH probe, EasyLink, and a TI 84 graphing calculator.  Vernier's pH probe can be connected to a laptop with a Go! Link and free Logger Lite software.  I have had good luck buying used probes and links on eBay.

This video has a brief introduction to microscale techniques.

Apologia and WA Physical Science: Circuits

Once the kids are grounded in the fundamentals, let them create circuits.  I am using Consumer Energy's circuit lesson because the photos are clear and it employs simple materials.  I have a copy of TOPS Science Electricity and have used aluminum foil, clothespins, and tape to create circuits.  You might try both methods.  Once the kids have the idea, we are going to make Squishy circuits with conductive and nonconductive clay.  Last summer at Mad Science Camp, they did not work well.  I had kids in one of my chemistry classes use squishy circuits for their science fair experiment and were able to get the LED bulbs to light.  It took a number of trials and batches of clay.  We are going to give it another shot.  Stand by for the results.