Schools provide a good way to boost some of your stats which play an important role in the game.
You can build up your experience points by spending Strength and Will.
Gold and gems can be used to increase your maximum Hit Points, Strength and Will. The base value for HP, ST and WL are 100 times player level, but these can be increased up to double the base value at Schools!
Future updates will include additional training options at Schools as well as new items that will allow players other ways to increase their stats.