Is the tat meeting a 'team' meeting? We have had a couple of those, do come prepared to speak about strengths and weakeneses your son has and strengths you see the program offering and where you think there are weaknesses.
I have always been asked to speak first at these meetings, so be prepared for that too. Have a simple 3-5 sentence statement worked out in your mind or on paper if you are more comfortable with that, stating pretty much the above - and what you hope to have happen for your ds.

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