This book is a description of how young people, Don and some mathematicians, solved problems which involve infinite series, infinite sequences, functions, graphs, algebra, +, - important mathematical ideas. At the same time they do a lot of arithmetic, and use pineapples, the tower puzzle, with science to math activities, and the use of other hands-on materials.
I love the concept of this book. I love the thought of making math, including calculus, accessible. I loved calculus when I took it back in high school. I wish I'd known more about it the previous year when I was struggling through physics.
However, this book could really have benefited from letting an English teacher proofread it. There are sentences that simply don't have all of the necessary parts. Like verbs. Or subjects.
It's a great concept, but it's written half in a rambling diary tone and half like a college textbook. I do still plan to give it to my brother for his birthday. He's an engineer with young children. I suspect he'll be able to look past the poor writing quality and delve into the equations more easily than I could.