Newborn to 10 months
A takeoff on the mobile, activity gyms typically feature a charming, brightly colored floor and hanging detachable toys that make sounds, play music, and sport tantalizing textures.
What Babies Learn: Like rattles, activity gyms help babies explore their environment through their sense of sound, touch, sight, and taste. Their motor skills also get a tune-up when they kick at, bat, reach, and grab for toys. When you put your baby down on his tummy, you'll also give him the opportunity to develop his upper-body and neck strength, a prerequisite for rolling, crawling, and other physical feats.
Game Plan: Newborns will start their mat-time fun on their back, gazing up at the toy charms. If your baby doesn't like being put on his stomach initially, "distract him with the gym's lights, music, and crinkle toys until he gets used to it," says Kristina McMorris of Clackamas, Oregon. She says her son, Tristan, 5 months, "loves tummy time now." You can also detach baby's favorite toys and hold them out so he can reach for them. At first, your baby might just make general movements toward objects. Eventually, he'll be able to reach out and pull objects forward.
A warning: Your baby might find her activity gym so entertaining, you'll be tempted to park her there. That's okay once in a while, but your baby learns best by interacting with you and other caregivers, says Goldberg.