I spent 2 days earlier this week dealing with another DOJ project. Kind of humorous after the fact.
http://blog.onlymyemail.com/us-department-of-justice-fbi-victim-notification-system/

http://www.onlymyemail.com/services/services_omekids/
It's $24/year for up to 2 kids, and is pretty customizable.
From their site:
Messages we block may be easily released for delivery upon parental review and approval.

"Lock-Down" mode (most appropriate for very young children) is an option which will only allow email delivery from senders who have first received parental approval.

Parental oversight may be enhanced by enabling "Parental Review" which saves copies of all email delivered to your children's OnlyMyEmail addresses.

Our "Kids Carbon Copy" feature will send parents copies of all outbound messages sent from a child's OnlyMyEmail account.

Those features can be toggled as you see fit.