How to Filter Posts in a Group on Facebookby Alan Sembera
Facebook group pages can be a great place to for people with similar interests to exchange ideas, photos and other information. When a discussion gets out of hand or members begin to abuse their posting privileges, though, the experience can be ruined for everyone. If you're a group admin you can put the brakes on this type of behavior by filtering posts before they make it on the page.
Click "Home" on your Facebook toolbar, and then select the name of the group from the sidebar.
Click the gear-shaped icon near the top of the page and select "Edit Group Settings."
Check the box next to "All Group Posts Must Be Approved By an Admin," and click "Save."
Check the group page periodically for an alert at the top of the page that indicates new messages have been posted and are awaiting approval. Click the alert to see the new messages.
Review each message, and then click the button with the check mark to approve the message, or click the button with the "X" to delete the message. You can also select the button with the circle to delete the message and ban the author from the group. If you approve someone's post, you can also click the "Automatically Approve" link to give the author permission to make future posts without prior approval.