Your middle schoolers are invited to participate in the NAIS Virtual Science Fair which features e-mentors (scientists and educators) who work with teams of one to three students, and virtual judges. It also offers the possibility of creating teams from two or three countries (STEM meets Global!) The best entries will compete for the "World Championship" Virtual Science Fair title (which this year was won by a student from The Chapin School and a teammate from Israel).
The cost is $300 per school regardless of the number of students taking part.
You can sign up for the 2013 Fair by contacting Dr. Whitney Elmore, the project director, at email@example.com