Once they had all the dry ingredients in the bowl, they mixed them up and made a well for the wet ingredients. The reviewed the terms solid and liquid and determined which ingredients fell into these categories. Once all the batter was mixed up the students made a prediction of what they thought would happen when they went onto the griddle. Some students predicted that bubbles would form with a gas inside!
Students moved to the griddle in back where a small pancake was placed on the griddle for each of them and they had the option of putting white or milk chocolate chips on top as well. Students looked closely for the presence of bubbles and made guesses about what kind of gas it might be inside. When the cooking was complete they were able to eat their creations and glue the directions of how to make the batter to their recipe.
Although the melting of the chocolate chips and the cooling back into a solid is a reversible change, the cooking of the pancake is not reversible. The reason this is not reversible is due to a few chemical reactions going on in the pancakes. First, when the dry ingredients are mixed with the wet ingredients, the proteins and
The reason is that baking powder is a mixture of baking soda (a base) and cream of tartar, calcium acid phosphate, or sodium aluminum sulphate, which are acids. When moistened, the acid and base react giving off carbon dioxide gas which are the bubbles that rise in the batter and leaves behind the holes that make the pancakes fluffy. Here is a great article and activity from Scientific American on what makes "Fluffy Pancakes."
The last reaction is what turns your cakes golden brown and gives off the sweet smelling aroma that attracts us to the kitchen, it is called the Maillard Reaction. This reactions takes place between the sugars and the amino acids in the proteins and goes through several rounds of chemical reactions to produce small quantities of hundreds of different flavors and colors, which is why seared meat doesn't look or taste the same pancakes. Here is a nice article and video from NPR that explains it further: 100 Years Ago, Maillard Taught Us Why Our Food Tastes Better Cooked
Click here for some fun facts about pancakes from Los Alamos National Laboratory.