Our DS8 is content to not learn at times, or appears to be underachieving but normally I find he is like that when school is at its least inspiring (which is a lot more than I'd like at the current school). The more interesting the environment is to him, the more he thrives on learning and turns to the exact opposite, that of an overachiever.
I think you will find out quite a lot of good information from Linda Silverman at the center. The center is a wealth of information (my son tested there). I hope she is able to give you some direction.
