So what would happen in Will Kenrith lost is leg at Strixhaven, a college in the USA?

There would be an out of court settlement for sure but this would not be the outcome.

Let's dive in. https://twitter.com/JoshuaClaytor/status/1390346417772933133

So any college (again, for the purposes of this thread we're talking about schools in the USA) would ask if Will was participating in mandatory academic activities.

The answer here is clearly no. Defeating the Blood Avatar was definitely extracurricular.

There would be conflicting evidence however, as some Deans told the students to get to safety. Meanwhile a Professor told Will and his sister to participate.

We have a hierarchy issue at play. A "reasonable actor" would listen to a higher ranking Dean above a Professor.

The Kenrith's could make a case that given the emergency nature of the situation that Will was following last known information.

If Garruk got involved (which seems likely) we might be subject to a conflict of interest involving Onyx and Garruk, which could get messy.

Basically, whether or not Will was participating in mandatory academic activities is a crucial point. Given the duty to care and the explicit instruction from high ranking deans, Strixhaven would have a decent argument that Will was not acting in capacity of a student.

BUT this took place on college grounds. More than that, it took place in a potentially dangerous location where there were no warning signs as to the danger.

Bad sign for Strixhaven.

What about force majeure? My guess is that Strixhaven's insurance policy would list "Evil Wizard Assault" under their "act of universe" clause.

This could mean Strixhaven administration was aware of the potential for such a cataclysmic event.

So we have a university that did not post sufficient warning about the known dangers of a campus space and a student who suffered harm in a potentially extracurricular activity.

My best guess as to the outcome:

Out of court settlement with no admission of fault for either side.
Signs posted warning of potential Blood Avatar.
Mandatory class on magical safety to be completed before anyone can enroll in Strixhaven.