Each pool has a commitment challenge.
For example: Raise your cumulative GPA by the end of the Winter 2017 quarter.
To join the pool, you chip in the buy-in fee (e.g. $20). These buy-in fees are collected into one giant pot.
Everyone in the pool who completes the challenge gets to split the giant pot of money evenly.
Those who fail to complete the challenge forfeit the buy-in fee.
Congratulations, you've completed an academic challenge, and earned some money along the way!