Right now if you google "zelda" a Master Sword will appear in the bottom right corner. If you click on the sword it will open a 1998 version google with a search of "zelda".

They clearly have the ability to disable AI in search but just refuse to.

If I understand correctly, they already exclude AI overviews for under-18 users in the EU to comply with local laws.

No. You can just append "&udm=14" to your Google search URL to remove AI overview.

This is software, there are no constraints. Technology is about political control and this is Google trying to exert it over school children.

They can be cute and say that the search results are AI, which while technically true is probably not what most people mean when they say they don't want AI. They could literally just disable the AI Overview at the top and that's what most schools mean when they say they don't want AI features.