saying "very many" is incorrect, even in english. This is coming from my mother who taught english for a living
colloquial english accepts very many
Does 'elever' not work here?
Generally, you're an "elev" in primary, secondary, and high school*, and a "student" in higher education.
* Barneskolen, ungdomsskolen og videregående
Kjempemange or særs mange, but not mange?
Because "very" needs to be translated.
I think 'there are a lot of students' would sound normal