In the news today, Disney admitted that their Baby Einstein videos don't actually make kids smarter and are offering a refund to anyone who bought one.
This seems a bit obvious, perhaps. Einstein himself didn't watch them when he was a kid, did he?
What does make kids smarter? According to this piece in the NY Times, "Parents and other caregivers teach young children by paying attention and interacting with them naturally and, most of all, by just allowing them to play."
Play. Makes you smart. Huh.