Our daughter, Adam's mom has a very high IQ and at the time her HS math teacher told me she may have been his best math student, ever. We'll Adam's mom was not nearly the math student as Adam.
There's a bit of a heartwarming story about this. Our daughter's HS math teacher was extremely disappointed she did not go to college. He had retired by the time Adam was becoming a math star with his photo and stories occasionally in the paper. Once when Adam was preparing for a big math contest, Mom called the retired HS teacher to see if he would work with Adam to prepare for the contest.
Adam and the retired HS teacher would meet each night and challenge each other working on complicated math problems. When Adam participated in the math contest, he got first in a multi-state contest. It was a testimonial to the retired HS teacher. He finally got what he wanted but he had to wait a generation. Our hats off to this great teacher.
God bless your grandson and your wonderful family.