A quick and simple search yields this. Some of the following that are highlighted have students ages 12-18. Some 11-18. Some even as young as 4 and 6 years of age. Can this off-topic conversation end, now?
So I looked into it, the Irish speak IRISH, not english.
which is actually a different language.
Google translate example:
English: My son is attending middle school
Irish: Tá mo mhac ag freastal ar mheánscoil
The translation of the word college (english) into irish gives "Coláiste"
The translation of the word middleschool (enlgish) into irish gives "meánscoile"
As such, in Ireland they do not use "college" to mean middle school. they use "meánscoile" to say middle school.
Also the question was whether people use the collective noun "college"
ex "my son (who is 13 year old) is attending college (referring to the word for a middle school)"
Not the whether there are middle schools with college in their NAME.
ex "my son (who is 13 year old) is attending a middle school called Midleton College"
That all being said... this is sufficiently
close to say the entire argument is likely based on a miscommunication.
Where he might have referred to "some middle schools have the word college in their name" and I misunderstood it as "in X dialect / language the proper word college means middle school"