HSM Birthday party! Need Ideas?

My daughter is turning 4 We are having a High School Musical Slumber Party ! There will be 9 little girls , youngest 4 , oldest 7. Two boys age 6. Need ideas for there age level. From everything to food, games , decoration and to serve cake or cupcakes ? Any Advice? She only 4 but love HSM , Cheetah girl's and Hannanh Montana. I was thinking of doing like a diney theme too so i can mix all 3 of her favorites.What do u think?