I would suggest hanging around the school and getting to know the other kids's parents, and even the kids themselves, but if you are working that could be hard.. Still, it is your best recourse, so if there is any way to juggle things to increase your local presence, I would do that.
My son has always been best one on one. By the time he was 6 or 7 he stopped going to most other kid's parties as he realized he really didn't like the parties. That is common with Aspies.
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Mom to an amazing young adult AS son, plus an also amazing non-AS daughter. Most likely part of the "Broader Autism Phenotype" (some traits).