Next, we took our eggs outside and played with the strength of an oval. I instructed the students to use one hand only, and squeeze the egg as hard as they could ~ but they had to apply equal pressure all around (example: don't just press hard with your thumb). The students were shocked that they could not break the eggs, as we all know eggshells are pretty fragile little things. But when you squeeze an egg in your hand (all rings must be off), its' strength is amazing. The strength of an egg lies in its shape. If you took a sharp object to the side of an egg, it puts pressure on the thin shell and easily breaks it. But squeezing it directs pressure into the egg, so that it compresses along, not across the shell.
In our structures unit last term, we learned that architects and engineers have used smooth curves, known as arches, to support the weight of structures for centuries. An arch directs pressure so that it compresses (squeezes) the building material. An egg is really and amazing piece of natural engineering.
We ended the day, celebrating Easter with jellybeans. I decided to let the students demonstrate their understanding of a "fair share" or "fractions of a group". I gave each small group a handful of jellybeans and asked them to figure out how to share them equally amongst each other. When the task was completed we discussed how the lesson was related to both fractions and division. Math with food is always full of enthusiasm!