The Crafty Crow has a great post up with links to 8 different cards for your kids to make for their dads. Our favorite (and most do-able for the kids abilities) is this one from Ramblings of a Crazy Woman:
SHANELLE is a mom to 4 (7, 5, 4, & 1) and temporarily retired from teaching elementary school to stay home with her kids. She loves making learning fun and exciting, in new and creative ways. Her personal blog is Just Barefoot
JULIE is a mom to 4 (6, 4, 2 & newborn) and former teacher who loves reading, teaching, creating, cooking and learning new things. Her personal blog is Rarely Home Mom.