Where's that better mousetrap, then? And I'm still waiting for my flying car.

Secundus has always been the inventor in the family. But eight-year-old Tertius is catching up. He's just quietly rearranged the boys' shared bedroom into a classroom, with their plastic storage crates for desks and a dry-erase sheet taped to the wall as a chalkboard. Each desk has a book, a Post-It pad (and I want them back!) and a bottle of Poland Spring. A larger teacher's desk faces the others.

I remark to Secundus, who has been studying Thomas Edison in school, that his little brother is following in his footsteps, but that Tertius is now the one putting all his energy into furniture-shifting. When S. gets involved in these projects, he tends to be the more cerebral overseer.

"You know what they say, Dad," he replies coolly. "Genius is one percent perspiration . . ."