Anecdotal, but in Spain kids don't take these tests seriously.
I remember when we were in school we would ask if the tests counted towards the final note for the subject and they didn't so we would just basically finish asap so we could do other things.
And I think this wasn't a "just my class" kind of thing.
Spaniard here. Yeah, not surprising — there’s a bit of a cultural fondness for sabotage, or at least for deliberately messing with things that are "official" but somehow unimportant.
And I think this wasn't a "just my class" kind of thing.