You can ask the school to do a Multifactored evaluation. Write them a letter and tell them your concerns. After the "MFE" is done, call an IEP mtg, with the team to sort out the evaluation, write new IEP goals and get the boy help-especially if he's slipping. Kids not only have to keep up, but should improve and if not doing so, then you have to go back to the drawing board. The school should test him after a formal request from you. Good luck.