Thursday, July 7, 2011
One of my favorite ways to start the school year
We start by discussing an egg (out of the refrigerator). *Note: You can do this with an actual egg in a clear plastic cup in front of the students, or just ask the students to discuss what they know about an egg from memory. I write down a few of the words they mention (cold, hard, white, etc.). Then I tell them that I have an egg that I took out of the refrigerator, but I explain that I changed the egg in some way. I bring out eggs that I have soaked in vinegar for 24+hours, and we begin to make observations. *Another note: The eggs swell up and become 'rubbery'. You have to see it to believe it.
I put an egg at each table, and I encourage the students to use their words to tell me what they see, smell, hear...and even what they feel (I do let one or two students 'smoosh' their eggs inside the cup, so that they can see what happens). The kids are fascinated, and I emphasize that I did something to change the egg---reinforcing the idea that we can change things, and setting the stage for our first experiment. I also introduce the idea that scientists make observations.
After we have compared the vinegar eggs to an uncooked egg, I tell the students that we are going to change the eggs again. I choose several of the eggs, and pour corn syrup into the cups---enough to cover the egg. I tell the kids that they have to wait until the next day to check the eggs. We make predictions about how the eggs might change. I put the eggs in a safe place where the students can't see them until the next day when they are "ready."
The kids are always excited to see what happens to the egg. When we examine the eggs, we see that the eggs have gotten smaller, and look 'wrinkly'. They also smell different.
Usually by this point, one or more students have voiced, "I wonder what would happen if we put the egg in ________?" I ask the students to tell me how we could figure it out, and it leads us right into the design of their very first science experiment! We might try to soak an egg in water, milk, soda....and we always record what happens.
I haven't mentioned all of the writing we do during this process---the kids are always excited to 'record' their observations. As for reading, this is a great book to use when teaching your kiddos about science: