Wow, JB, that's so exciting!

Do you know Don Cohen's books? He's at . I wonder if his stuff might interest your son--there's the main book (Calculus by and for Young People age 7 and Up), and one called something like "Changing Shapes with Matrices" that was well-loved here (and that sounds like it might have something to do with what you're currently reading). (Sadly [well, sad in this context, anyway], I am Humanities Woman, not Math Woman, so I'm not sure whether this really relates to what you are discussing! But on the off chance that he might like it, I'm willing to risk the public humiliation!!!)


PS And good on you for reading him what he likes at bedtime!!