I am a level 24 balance student who also studies ice so I would know a good solution for you. Balance school offers a spell, I cant remember the name of it, that you cast on yourself. The spell gives you + 25% damage on your next attack, no matter what school its from. There is also an ice spell called Ice Trap. Ice Trap will give you + 35% damage for your next ice attack on the enemy you use it on.