Anyone know of a good curriculum or supplement for logic and critical thinking for a gifted 3rd grader? I am finding a few things but his grade is on the border line of most of the stuff and I'm not sure whether to jump to the next level or stay with his age. I've looked at Building Thinking Skills mostly. I am sure there is more out there....maybe even a bit cheaper? I have found some things on e-bay, so price might not be such a big deal. Any ideas are welcome!