Translation:The students listen to their teacher.
Very good remark.
Ascultă actually has two distinct meanings. To listen as in to concentrate on hearing something, for example:
Eu ascult o melodie. (I listen to a song.)
El ascultă ce spun eu. (He hears what I say.)
Among a few other things, it means to obey. And in cases like Elevii ascultă de învățătorul lor. it is more of an they obey instead of actually listen as if he's saying anything. In the later case we would say Elevii ascultă ce spune învățătorul lor.
We even have the adjectives ascultător and neascultător meaning obedient and not obedient. El e un copil ascultător. El nu ascultă de mama sa.
In other words, the translation The students listen to their teacher. is not actually correct here.
Thank you, Razvan, for this excellent explanation! I taught in Romania for a couple years, and would often be a 'guest teacher' in the classes of other teachers. Teachers would occasionally tell me that a certain class I was about to teach was a really GOOD class -- but what they meant was that it was a completely silent class. In light of that, and in retrospect, your definition of ascultator makes a lot of sense within Romanian educational culture. Limba noastra e o comoara!
Bonus fact: remember when I said it means to obey among a few other things? There's even another meaning for ascultă in the educational culture:
- Profesorul mă ascultă.
Which means that the teacher is oral testing me. In our culture such a test can be either announced or unannounced, resulting in a mark or not, using the blackboard or not.
Other more complex examples:
Învăt pentru ca mâine mă ascultă la matematică.
Am luat notă mică pentru că m-a ascultat și nu am știut.
Profesorul ne-a ascultat ieri pe toți.
And a very interesting one:
- M-a ascultat pentru că nu am fost ascultător.