A few points to keep in mind:
• Excessive advertisement banners or flashing graphics on a website which are distracting will not make the cut. A few ads are okay.
• The theme must be related to mathematics, computer science, physics, etc.
• You must have some original content. This website, and especially the Games & Links page, is a gateway to other resources. A gateway to another gateway is not helpful to anyone.
• Your content must be free of identity politics.
• If your site requires paid membership, that's fine. Some useable content must be free, or have a fully functional free trial period.