Here at the Academy our students are divided up by "Years". We do not have grades, although they do share some similarities.
These are the youngest members of the Academy, who've just arrived. These students are either 13 or 14, and have minimal control over their powers.
These students are no longer on the bottom. They could be compared to a sophomore, as they often give the First Years a hard time, even though not long ago they were in their shoes. These students are either 14 or 15 and have slight control over their powers.
Third Years are your "juniors." They have been around a while and know the Academy well. They have most of the teachers figured out and know what they can get away with. These students are either 15 or 16 and have moderate control over their powers.
Years 4 & 5
These students are at the top of the food chain. They are the leaders of the Academy. They're now seasoned veterans and know their way around the school. Year 4's are either 16 or 17 and have fairly high control over their powers. Year 5's are usually 17-19 and have nearly full control of their powers.