At this point your child should be adjusted to the new school year. He should feel comfortable with his teacher, his therapists and anyone else who will be spending time with him.
Parents and caregivers should be involved as well. It benefits your child when the faculty at school knows that there is an active adult invested. Take the time to read the daily log that comes home with your son. It is not necessary to write a lengthy comment if all is going well. A scrawled thank you with a smiley face does the trick. I sometimes buy stickers and stick them on. Stickers are always fun, no matter the age of the recipient.
Now is a good time to show the teachers how much you appreciate them. Don't wait for the holidays when your gift or personal card is one of twenty five, it doesn't stand out as much. A gift does not need to be expensive. A Starbucks gift card makes a great gift. A gift certificate for a local manicure is always well received. I've filled little plastic containers with jelly beans and that too was appreciated. It's not what you buy, it's that you are acknowledging the effort and love that the teacher and therapists are investing in your child. An investment must be nurtured, and your child is your greatest investment.