"Shine could do it temporarily. Earth maybe could figure out how to do it permanently but you'd have to know a lot about how Amentan hair colors work."

"I mean, we know the heredity patterns reasonably well, but we couldn't isolate the gene sequence or anything."

"...I don't know what a gene sequence is, that's not the - right kind of knowing."

Shrug. "It's not about the hair anyway. Just, if you got magic that did a dozen miscellaneous medical things and changed the hair people might buy it as a - hereditary uncleanliness scouring spell. That's always been Aitim's endgame."

"Earth does very miscellaneous medical things but it's Water you want for - poison."

"Where can someone get a comprehensive overview of magic, its theoretical limitations, etc etc..."

"Well, I'm going to found a school. ...I might need somewhere to put it that is not my redful rainforest. Even though I will want to take reds if I can."

"Sure, but people who can't do it and just need to know what it's capable of are a different case. A university here'll host you."

"Even if I take reds? And even if - depoisoning them - doesn't fly?"

"There are access tunnels, we can work something out."

Elementals have 1-2 elements very strongly and mages have 3-12 at varying strengths, never as strong as an elemental. (12 is almost unheard of but we are pretty sure it has happened to at least one human.) What can be done, especially by human mages using elements in combination, is still being studied. General domains of the elements are known to be:

Adamant: Metal, warding/defense, magnet sense, artifact components.
Air: Air, weather, insubstantiality, scent, very specific respiratory healing.
Earth: Soil, living things (any work on living things with pure Earth requires a lot of detailed knowledge), life sense.
Fire: Fire, prolonged youth, infection-specific healing, warmth sense.
Glass: Glass, vision, breaking things, artifact components.
Ice: Ice, cold, stasis, state sense (solid/liquid/gas).
Lightning: Electricity, fast but not instantaneous travel, hearing, anaesthetic.
Shadow: Darkness, shadow-scrying and shadow-walking.
Shine: Light, invisibility, light-scrying, expensive total instant healing.
Stone: Rocks, weight, tremorsense, longevity, artifact components.
Water: Water, water-sense, poison and dehydration healing, weather.
Wood: Plants (more specifically and less knowledge-dependent than Earth), malnutrition-related healing, plant matter sense, artifact components.

All elements afford at least one special or improved sense. Human mage affinity is graded on a five point scale: none, enough to use the sense at all, enough to incorporate the element into an artifact without elemental help, enough to use other applications without elemental help, and a best affinity which seems to be consistent in strength across human mages (someone could have only three affinities but their best one would be as good as the best of someone with ten).

Greens the world over are fascinated. People start eating more seaweed if expecting.

Probably unlikely to be seaweed in particular for a different species.

Can't hurt, though! 

True.

Places fuss over registering their mages. Anitam and several other countries pass a law that if red parents hand over red mage children they can be refunded their credit for next year.

Maurabel does not say whether she or any elementals are healing reds of things or smuggling them to her rainforest.

She doesn't ask Aitim for an answer.

Maurabel works on school things! What will she need to know to operate a school here?

Here's how the school system works here! It's caste-segregated, is hers going to be? 

Seems like magic should be a thing you can do regardless of caste like being a house spouse or reading novels or something. She will have the segregation necessary to make sure that if somehow a red student turned up from somewhere - it's a big world - she would not break any laws by letting them attend lectures with an Adamant bodyguard.

How's she going to handle some students being much faster and more able than others?

There's only one of her, she can't teach that many separate classes.