Buy some neat toys they can play with at your daycare.
I'm getting a play tent with tunnels. A bit of an investment, but I know they will enjoy it, and it won't get left in the car, or tossed underneath a bed, or torn up due to lack of supervision.
If you feel bad not sending them home with something, buy some books from a scholastic book order and send those home, but save the rest of your money for something they will use all the time. At your house. That's probably where they spend a majority of their waking hours anyway.

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