Math-
Play any type of card game or strategy game together!
Try these websites (both are free):
Language Arts-
-Read 20 minutes a day
-Visit the library
-Write in a diary or journal
-Write to a friend or relative (postcards, emails, etc.)
Science-
Check out kid's activities at the Audubon: http://www.mtacec.org/
Art-
Visit YAM: http://www.artmuseum.org/