Yes, what HK said. I'm currently trying to afterschool my preschool aged DS at home (he will be in K next year), at his fervent request, and it is freaking impossible, because he has the reading skills of a third or fourth grader, math abilities somewhere in the 2nd grade range (except he's never been taught money and time, and they spend a LOT of time on that in the early grades), but his writing and spelling skills are early/mid K, and he has the life knowledge of his true age.
I am unwillingly considering that I may need to homeschool him next year, in which case I think we will do:
--some handwriting/writing practice on grade level (Maybe Handwriting Without Tears, since it seems well-liked)
--reading chapter books and science books broadly
--fill in the circle reading comp, without writing, at his reading level (this is not easy to find and a lot of it is bad)
--some of the science experiment kits available
--some math workbooks, but this is going to be hard and I will need to cherrypick)
--logic puzzles, Sudoku, mazes, find the missing X books (he loves Life Picture Puzzle books), lots of high-level board games, ThinkFun logic games, card games
--geography work because he loves it
