Mary Claire brings home a puzzle to solve for her Focus class each week. Sometimes she asks me for help. I enjoy trying to guide her to figuring it out herself.

This week’s problem was how many pizza combinations can you make using zero to five different toppings: sausage, mushrooms, pepperoni, peppers, and onions. Mary Claire set up a grid and made X’s next to each ingredient to come up with all combinations. She discovered this pattern:

1 that is plain

5 that have 1 topping

10 that have 2 toppings

10 that have 3 toppings

5 that have 4 toppings

1 that has 5 toppings

She added them up for the answer, 32. Danny noticed the pattern and said, “That’s Pascal’s triangle.” He drew the triangle. See: All You Ever Wanted to Know About Pascal’s Triangle and more.

Mary Claire recognized the triangle of numbers and said she recognized it. In her class they called it the Period of Mystery. I asked her, “Why do you think they call it period?” She said, “Because it is shaped like a period.” I then realized her mistake. “You mean, Pyramid of Mystery.” She agreed that name made more sense, given that Pascal’s Triangle looks more like a Pyramid that a period.

I just want to know when did they start teaching third graders about Pascal’s Triangle?