Exercise, teach "Give", and, I agree, NILIF wouldn't hurt.

Exercise = simple. Take her for a jog, play a game of fetch, play some mind games, play hide and seek, etc.

Teach "Give" = Give her a low value treat, like a carrot stick. Hold a high value treat, like a piece of boiled chicken in front of her nose. As soon as she loosens her grip on the low value treat (in this case, the carrot), say "Give" and take the carrot. Immediately give her the chicken. Repeat repeat repeat. Eventually, you can start trying "Give" with higher value things, like stuffed toys and chew toys.

NILIF = Nothing in Life is Free. It'll help teach your dog what the rules are and who's boss: http://www.nomorehomelesspets.org/be.../dog/nilif.htm