Filtering/Security

Hi all,

I want to incorporate GoogleApps in my classroom, and eventually branch out into the rest of the school (grades 6-8). I have been getting some resistance from administrators in regard to security/filtering. Since you guys have experience with this, what have you found that works and doesn't work? Have you had issues with students posting inappropriate things? What types of policies do you have in place, and how much does Google have built into the Apps for Education in regard to security/filtering?