I do not really have advice for you but just wanted to say my DS who is turning 7 next week and is in 1st grade does something similar. He was really into reading Encyclopedia Brown books for the last few weeks - he is the type who likes to finish a series. So he took a couple of them to school last week to read to a buddy during reading time but no one in his class wanted him to read that book. So this week he wanted to take magic tree house books to school - the ones he had finished with more than a year ago - I asked him why and he said his friends don't really get the mysteries and how they are solved in the Brown books and that he would rather read what his friends like. In math too he happily does some simple addition subtraction problems - drawing circles and crossing them out and labeling them even tho he is working on the AOPS Pre Algebra book now with a tutor at home. This is a kid who tested in the 4th grade level for reading and math in WJ III when we tested him earlier this year. His IQ scores don't match up to his achievement scores I am not sure why (WISC 117). His tester said he was co operative. Maybe he is one of those normal IQ high achieving kids. Do you think he is trying to fit in with his classmates? Good Luck !
