Friday afternoons are set aside at our house this school year for fun activities like art, crafting and science experiments, during Sunny-boy's naptime.
The other day I came across this simple experiment in a free e-newsletter from Krampf's Science (a favorite and fun resource -- plus, check out his membership benefits, as well!), and decided to set aside my previous plans and develop a fun afternoon around it!
We have tons of plastic eggs, which started out several years ago as fodder for simple Easter Egg hunts, and ended up becoming a permanent fixture on the toy shelf. The children use them for pretend cooking (SB in particular likes to tap them on the edge of a bowl and "crack" them open), and for hiding small toys, accessorizing block play, filling and dumping trucks, picking up and releasing with tongs and of course, spur of the moment Easter Egg hunts in the living room. A couple of years ago, Step 1 and Step 2 found that if you squeeze the bottom half of a connected plastic egg, the top will shoot across the room; hilarity ensues. (This activity has special appeal to The Chief, who can be counted on to engage in Egg Wars at a moment's notice.)
Krampf's experiment involves discovering whether you have a raw egg or a hard-boiled one, following some simple observations. I knew Junie B. would catch onto the concept quickly with just a demo and a verbal explanation, but I figured Taz would appreciate a more concrete approach.
So, before introducing the real eggs, I set up a similar experiment using plastic ones!
In one egg, I put a metal marble from a magnet toy set. (I had wanted to use a small super ball, but naturally I couldn't find one. I probably got rid of the one I was thinking of in a recent cleaning & decluttering frenzy; that's usually the way it goes.) :)
The second egg, I stuffed solidly with playdoh (made, by the way, from this simple and fool-proof playdoh recipe I found awhile ago via The Crafty Crow! We added glitter, which didn't really photograph too well...) :)
It was easy to see that the marble in the egg continued to move when the egg stopped, and it was equally easy to see the effect of the playdoh on the stability of the other egg. I let the children make their own general observations, which I wrote down, and then guided them through the actual experiment observations (spinning and stopping the eggs). Again, I recorded their observations for them. We talked about what raw and hard boiled eggs were like, and discussed which of the plastic eggs might be more like a raw egg, and which more like a hard boiled.
From there, the children were given two real eggs, and were to use their observations about the plastic eggs to make comparisons with the behavior of the real eggs, and then predict which egg was the hard boiled one.
It actually worked great, and the experiment flowed very well! Of course, Taz smelled the eggs first, and immediately said, "This one smells hard-boiled." (I didn't count on that -- it was true!) Still, the real eggs behaved very like the prepared plastic ones (right down to the significance of smell, now that I think of it, since the playdoh was colored using grape koolaid mix!), and it was easy to facilitate a concrete level of understanding.
And, of course, as Krampf always likes to recommend (really, get the newsletter. It's loaded with personality!), the kids got to eat the experiment when they were done! :) (The hard-boiled eggs, of course. Not the playdoh.)
After that, we experimented with spinning the plastic (empty) eggs on their ends (the wider part down), and had our own variation of "Battling Tops" -- using a large pasta bowl for an "arena," to see whose upright spinning egg could reign supreme!
Finally, we had (the obligatory) Easter Egg hunt.
It helps to know how many eggs you've actually hidden (since the hider often forgets where he or she put them!); we controlled this by filling an empty egg carton, and only hiding those.
All in all, I'd say this first formal "group" experiment was a success!
Related Literature Extension: In Encyclopedia Brown, Boy Detective, there is a story ("The Case of the Champion Egg Spinner") about a kid who, ultimately, is caught cheating at egg spinning contests. This experiment explains how Encyclopedia was able to find him out!