Althea and her friends (Kiara, Sofia, and Aiden) begin to explore the history and ideas of calculus, with a bit of help from Mom. The schools are online because of Covid, and they're all homeschooling for the duration. They've only taken one year of algebra, so Mom brings in lots of activities that review algebra and geometry concepts.
Activities
Triangles in rectangles: You can use an online geoboard to make triangles
References