We started with a regular yellow cake batter. You can use a cake mix, or your favorite from scratch recipes. Then, we divided the batter into six bowls, and added food coloring to make the colors of the rainbow. This is a good color mixing exercise for the little ones, but it does mean feeding your children a lot of artificial dye.
Once we had the colors mixed, we blopped them one on top of another into the cake pan, and baked it as normal. I realized after we started blopping, that we had goofed up the order of the rainbow - but, oh well.
Frosted, the cake looked liked any old regular unassuming cake. But once it was sliced, there was a rainbow surprise.
While we had the food coloring out, I decided to give a 30 second chemistry lesson - also known as magic milk. We took a bowl of whole milk (any milk will do, but this experiment works the best with the highest fat content you can get).
We added four drops of food coloring, trying not to let them touch.
Then, we added one drop of dish soap to the middle of the dish, and watched as the colors danced and mixed, as if there was invisible hand stirring them. I started into my prepared speech on surfactants, surface tension, and fat eating enzymes (you can find a really good explanation of the science behind this experiment at www.chemistry.learnhub.com/lesson/3809-chemistry-experiment-magic-milk), but being full of sugar and red dye #40, they were more interested in the "magic" than the science.
So it was rainbows, cake and magic tricks. Was it art, home economics, science, or a party? Let's just say it was just another rainy afternoon at home.
It's great to be a homeschooler!