9 Yr Old Girls Suprise Partyq

Hi My little sister is turning 9 and its in April we are having an out doors party but we dont know what to do we are having a dj so its very all and out there are numerous tables with name plates she is having a sorta grand entrance we need ideas thoughs on how to keep the kids entertained invites go out next week.
I am 10 and since my mo is a workaholic I am the party planner please help me.You can also email me at dkuhlor@yahoo.com or at aim.com my im is dkuhlorTTYL
Denisha