If there is a clearer, more easily understood calculus book available, I have never seen it, and I have seen many (I teach math at the university level). If you want to teach calculus to your homeschooler, get the first or second editions of the text (the first is better written, but it contains only the material from first semester college calculus and maybe twenty-five percent of second semester calculus while the second edition contains all of "calc one and calc two"), the answer book, and a scientific calculator. That's all you will need.