Mathematics is a very important subject. Lance's level is actually just average; most of the related knowledge has been returned to his teacher. However, he understands how to manipulate numbers and symbols to simplify a complex system.
Occasionally, he organizes public classes where real experts teach them.
Grendel teaches them to identify plants, and covers basic herbology, or sometimes common potion concoctions.
Paracelsus teaches them human anatomy, emergency aid, and some medical knowledge.
Boudica teaches them hand-to-hand combat, Reynard teaches them weapon techniques, and Dismas teaches them shooting...
Perhaps Beggby can take on the role of a chemistry teacher? But judging by his social anxiety, he might not be well-suited.
Anyway, besides basic courses, there are many other lessons that fill their schedule, mainly depending on the availability of teachers.
