DS5 (will be K age in the fall) is doing some afterschooling with me at his request. We are mixing it up, but I have some Singapore books (he is doing 1B) Spectrum Reading grade 1, Mailbox Math grade 1 (this isn't great, actually), and some Kumon books. He also likes kids' Sudoku and various "puzzle" and maze books. He likes to play with DD's old Flashmaster. I haven't been having him use the computer much. I also think I will probaby do some Handwriting without Tears this summer. We also play a ton of games. ThinkFun makes a vast variety of solo logic games--DS likes Rush Hour right now.