Friday, June 17, 2016

Messy Science: Erupting Foam

Recently all three of my kids have become fans of the Amazon Prime show "Annedroids," which follows roughly 12 year old Anne, two friends, and a trio of adorable androids as they use science to solve a variety of problems. My own credulity is stretched to the breaking point as I try to pretend it is possible to for a pre-teen to create self-directed, learning, and emotional robots out of parts found at a junk yard, but the kids love it and it seems harmless enough.
Anyway, in one of the early episodes Anne and her androids created what she simply termed a "chemical reaction" from common household ingredients: hydrogen peroxide, dish soap, and yeast. The results, which were probably just a wee bit exaggerated for TV, were spectacular, with pink foam exploding all over poor Shania, not once but twice in the course of the episode.
Needless to say, my kids have been clamoring to try it ever since.

Here's what we did

Gather materials

* Hydrogen Peroxide (the 3% solution in the brown bottle you can get from the pharmacy section at any store for under $1 is fine)
* Dish soap
* Packet of dry active yeast
* Warm water
* Large container (pitcher or clean 2 liter soda bottle)
* Small cup


The episode did not give any measurements, and the characters performed the experiment a couple of times with different amounts anyway.
So we just went for it!
1. We took everything outside and placed it on a tray
2. I proofed the yeast by adding about 3-4 Tbsp of warm tap water to the yeast in a small measuring cup. Lucy stirred this mixture with a stick
3. I added a few drops of food coloring to the pitcher
4. Grace poured in about 3/4 of a bottle of H2O2 (aka Hydrogen Peroxide)

5. I squirted in perhaps 1 Tbsp of blue dish soap
6. James poured the yeast mixture into the H2O2 & soap mixture.


As expected, the results were not Quite as spectacular as on TV, but they were satisfying nevertheless. At first I was afraid all we were going to get was a couple of inches of bubbles in the pitcher (which was only about 1/3 full of H2O2.) But over the space of about a minute, the foam grew and grew and grew until it overflowed the pitcher and even my shallow tray. (Yes, I was very glad we'd done it on the porch!)

The kids were pretty excited, especially 3 year old Lucy who had a blast flinging the (surprisingly warm) foam about for quite some time. In fact, we all had fun playing with the stuff for maybe 15 minutes before I made James drag out the hose and spray off the mess.

So, Why?! 

According to, the reaction occurs when the yeast steals oxygen from the hydrogen peroxide. The reaction occurs so quickly that millions of tiny oxygen-containing bubbles are formed. The reaction is exothermic, meaning that it generates heat (releases energy), but not so much in our experience that you're in any danger of getting burned. The resultant mixture is just soapy water, so it's safe to play with and wash down the drain.
I'm going to have to admit, though, I couldn't interest even James in the "why" of the whole thing: they just wanted to see things foam up!

Friday, June 3, 2016

Eleventh Hour Mini Unit

We needed a break from "normal school" at the end of this week. We've been doing a lot of worksheets lately, and my 1st grader is Not Impressed. So when I announced that we'd spend school time today trying to solve the mystery of "The Eleventh Hour," he was thrilled.

We picked "The Eleventh Hour" by Graeme Base up at the library last week when I happened across it and recognized the author's name and style from "Anamalia," a book I loved so much that I bought a copy for us after giving away one to my niece!
If you've never explored a Graeme Base book, you are definitely in for a treat! The rich, intricately detailed, and humorous illustrations make them a real joy for any age.
"The Eleventh Hour" has an added bonus: an old fashioned "whodunnit" (non-violent, thankfully!) occurs inside the book's pages which you, the reader, are asked to solve. Unlike Agatha Christie, however, where Poirot always manages to keep some critical observation to himself, here the mystery is actually solvable using a combination of visual, textual, and even coded clues.

James started our "unit" last night when he plucked the book out of the box and started reading it out loud to his 5 year old sister. While he was able to read most of the words, the rhyming and moderately advanced text put the story - not to mention the mystery - a little outside their grasp. I read it out loud a second time, and we took a quick pass at the mystery. While I found some coded messages that could be untangled without pen and paper, the mystery itself remained just that after the first reading. Thus my spur of the moment decision to replace worksheets with detective work this morning.

A note on grade level:
My oldest is a first grader, so I took care of most of the mechanics and lead most of the discussion and ideas. I think a 4th or 5th grader might be able to do most of these steps independently, although actually recognizing some of the codes for what they are may take adult assistance.

Here's what we did

1. Created a timeline of the birthday party, graphing which guests were present at which events. Both older kids helped here. We even got in a little clock-reading practice.

2. Solved a tic-tac-toe code, mirror writing, backwards writing, and some simple scrambles without pen and paper

3. Used pen and paper to solve letter substitution codes.  I had my first grader take dictation on some of these. I think with a little more time I could have taught him the process of actually deciphering some of the simpler codes, but we had both some time constraints and a lot of chaos from an impatient 3 year old in the room.

4. Identified Hieroglyphics and Morse Code puzzles which we will probably work on later.

5. Fingered our suspect and then used our guess as the key for a "shift" or "Caesar" cipher on the last page, which, when solved told us exactly how the crime was perpetrated.
This last cipher was a really long one, and I got tired of it less than half way through. A quick Google led me to this Caesar Cipher Solver. (No fair using it without figuring out the key first - but it Could do it for you!)

Now, did it take all of that work just to get the answer? Well... I don't want to give anything away, but it was my pre-reading 5 year old who found one of the critical clues. My first grader also spotted one of the cipher keys we needed for another clue.

All in all we spent about two hours, maybe a bit more on the project, including reading through the text a couple of times on different days.
My oldest stayed reasonably engaged (at least until we got to the long, boring decipher at the end!), but my kindergartner was done after 30 or 40 minutes.
Again, an older elementary kid could probably figure out some of the simpler codes, and a motivated middle schooler could probably get through most of them.

Thankfully, Base also includes a detailed description of every code and clue in a sealed section at the back of the book. If you get stumped or just want to know what he was thinking on a particular page, you can always refer here!

I hope to use this experience as a jumping off point for some more code / cipher projects. They're not only fun, but I'm guessing I can sneak in quite a bit more writing practice than he's usually willing to do without a fight!