The idea of a game about dealing highly illegal drugs candies at school can be fun, however...
Maybe I'm doing something wrong, but all the students are offering a price for the first candy which is less or equal than its shop value, so I can't really progress.
Price setting can also be improved. Now clicking on candy overrides what you just previously entered on the right, which is annoying, but then when you start typing the price again, it just adds numbers instead of overwriting, making the price ridiculously high, so you first have to clean it... maybe it would work better with choosing only how much you want to add to the price, something like [+1] or [+5] buttons, or even in percentage. That way you won't even need to change it when candy selection changes.