Sorry for the very late reply! Itch has a "collections" feature that you can use to organize your projects. If you sort your games into these collections, they'll appear as they do on my profile. That means you can create a "Game Jam" collection and your game jam games will appear grouped on your profile.
To do this, first go in your dashboard. From there, open your games' pages and click "add to collection" on the top right corner of the page. From there, you'll be able to create new collections/add your games to existing ones. Make sure your games are also hidden from your profile if you don't want them to appear twice.
Hopefully that helps! Let me know if that isn't clear enough.