If this
https://www.openstreetmap.org/way/293868620
is one school now, you should add a name and other info to this feature.

These two schools were incorrectly tagged:
https://www.openstreetmap.org/way/293868619
https://www.openstreetmap.org/way/639718964

To map a school you need at least two tags:
amenity=school + name

They were split. I mean, it was just a name added to a building, so it didn’t count as a school because it didn’t have “amenity=school” tag.

Look at: http://openpoimap.org/?map=amenity&zoom=16&lat=54.71907&lon=-3.49187&layers=B00FFFFFFFFFFFFFFFFFFTFFFFFFFFFFF
for example.

You can read
https://wiki.openstreetmap.org/wiki/Tag:amenity%3Dschool
how to map a school.