rahimnathwani 44 minutes ago

I like how Math Academy does it:

- each lesson or review or quiz has a target number of XP

- if you do it perfectly, you get the target XP plus 2

- if you do it almost perfectly, you get the target XP

- if you do poorly, you get fewer XP, and can even get negative XP

This last eliminates any incentive to guess or rush (at least in the cases I've directly observed).