This is the email I got from them about this.
Thank you for contacting Coolmath Games and showing interest in our game jam! When you submit a game to this game jam, we DO NOT take ownership of the game. Developers will still maintain all ownership of their games. When we select our 3 winners, we intend to promote those games on our financial literacy page and there will be a conversation of getting exclusivity for it. However, games that are not selected as winners are still the property of the developers.
This portion of the rules is meant to use the games as a way to promote and celebrate the creations from the game jam. When a game is submitted and it abides by our rules, your game will be featured in the Submissions on our game page. We own the submission of the game used in the jam, but this does NOT mean the games become our property. We have no intention of retrieving the source code from the games or taking control of the game's IP in any way.