The Important Rule:
The only real rule is "Don't be hurtful or harmful", breaking this rule will get you banned.
Now that's out of the way, here's the FAQ:
What should/can I make for Chess Jam?
Anything you want. It can be a game, a comic, a dance, a letter to a pen-pal, a song, anything!
I'd only suggest you take "Chess" as inspiration, whatever that means to you.
Will there be a winner/scoring/prizes?
This jam is 100% non-competitive, unless you and your friends want to decide on some kind of competition amongst yourselves.
As for prizes, you get out exactly what you put in - hopefully you make something you are proud of, or gain some skills you can use in the future. Mostly I hope you can just have a good time taking part and that's prize enough IMO :)
Is there a deadline?
Submissions are open all through April.
You are welcome to keep working on your game beyond that but you won't be able to submit new itch.io projects. (I'd keep the jam going indefinitely if I could be I don't have time to moderate never-ending jams sorry!)
Can I work on an old project?
You can work on anything even if you didn't start it during the jam.
Do I have to work solo or can I work as a team?
You can work however you want to!
If you're looking for collaborators then go to the 'Team Up!' part of the jam community.
Where can I share my progress?
I have made a category for you to post in here.
You're welcome to share your progress anywhere else but I can only enforce the important rule as a moderator here. (Tho I will be appearing in #ChessJam on twitter from time to time)
That's it, if you have any other questions, ask below.
I hope you have a wonderful time with the Jam!