7 年级的儿子进了州mathcounts

My son, a seventh grader, passed the chapter test and will go to state Mathcounts in March. This is his first time, as his teacher did not consider any 6th grader last year. We do not know how to help him. Any tips for us to start getting him trained?

He likes the questions so far, and he is very good at countdown. He got 7 out of 8 questions at Target round, which is wonderful in my opinion. He needs to do better in Sprint round, but how?

Thanks a million.