@Yaarel Interesting idea, I will have to think about how high I want the education to go. DnD sort of has this bizarre contrast between the idea of wizards studying for decades and decades to learn the secrets of the multiverse... and being able to go from Level 1 to 10 in 100 adventuring days.
Heh, you know how it goes, ... those who cant, teach.
More seriously.
D&D levels can correlate well the amount of power of a character compared to the size of the community where that character is prominent. (Magnitude 10 ^ Level/2. Examples. A level 12 character will be wellknown and influential to about a million people, namely the size of a medieval nation or a mighty city. A level 13 character will be influential to about three million people, and level 14 10 million people. At level 1, a character is influential to about 3 people, usually family including friends. At level 4, the student influences about 100 people, thus is prominent in the Wizard college.)
It is ok if ‘precocious’ students learn quickly and test their skills in the battlefields. While others take a longer time to advance.
Also, because the instructors might have special responsibilities (to the ruling council of the town, for example), the instructor might hand pick certain competent students to do dangerous missions.
The Harry Potter-verse conveys the idea of the students being in genuine danger while learning their magical skills.
Especially for a medievalesque setting, this feels likely.
Likewise, a Wizard academy is likely to be a military academy, training students in magical fightingstyles, while others are training in sword, axe, spear, and bow fightingstyles. So, even important missions can be possible for these young wizardlings.
Plus, the real secrets of the universe, such as the Wish spell, require the highest leveling tier to even begin to explore.