Practice passing: At this age babies are getting good at picking things up, have probably developed the ability to "rake" objects with their hands, and are beginning to transfer things from hand to hand. Fine forefinger or thumb control won't be developed until about 9 months, but you can get baby started by letting her try to feed herself (finger foods, not those that require a fork or spoon). Be forewarned: it's a messy proposition and you'll need to supervise her closely in case she begins to choke.
Let her taste her world: At this age babies experience things primarily through their mouths, so it's great to give her a variety of toys that she can gum or chew. Since she can probably sit up now, an activity saucer (like a walker, but without wheels) can be a good place for baby to sit and explore toys.
Explore cause and effect: Your baby is probably gaining a growing interest in cause and effect — "I push this button and I hear a sound." Offer her an array of toys that cater to this new interest.
Practice standing: By 9 months baby may be pulling herself up to stand or may stand with assistance from you or a stationary object. Help her do this by providing a sturdy toy — a play shopping cart or activity cart — but make sure your house is baby-proofed, that stairs are gated and all objects she might pull up on are well anchored.
Share your world: "If you're excited about something, your child is going to learn about it and be excited about it," says Chernoff. Talk to your child about the things you like to do and involve her whenever possible. "This is especially true for dads, who are sometimes a little awkward with babies," she says. "You don't have to figure out what baby likes; you can share what you like." If you enjoy hiking, take baby with you. Not only will it help you continue to do the things you enjoy, but it will also give you something the two of you can enjoy together.
Make music: Even though baby probably has a room full of fun toys, she'll most likely get a big kick out of banging on a pot, pan or plasticware dish with a plastic spoon or knocking down a plasticware tower, says Wallace. Babies are also developing better control of their fingers so toy pianos and toy phones are usually a big hit and a developmental boon.
Explore emotions: Your singing can take on a new element now that baby is ready to start learning about emotions. Try singing "If You're Happy and You Know It" — you'll not only introduce the concept of happiness, but you'll also be helping to develop body awareness and fine motor skills, says Wallace.
Swim: Baby might not be ready for the breaststroke yet, but swimming "classes" offer a good opportunity to get baby used to the water and to experience the sense of floating while at the same time bonding with you and building dexterity. Plus, you'll get a kick out of seeing baby explore water for the first time. Music and gymnastics classes are also good.