Does this mean, they ask the teacher questions, or more like they question the teacher's authority?
Is this why the teacher threatened the students? (referring to another sentence in this set...)
Is fear liom an foirm seo. I would have used "Cuireann na daltaí ceistanna ar an múinteoir" before using the "Ceistionn x" form, but we all know many ways to say the same thing, so it's good to be aware of another way you may hear it phrased.
Based on this discussion I think so - that had been my answer, and I reported it.
"Cheistigh sé san áireamh mé, he put questions in arithmetic to me"; and "Cheistigh sé díom cá raibh mé, he asked me where I was": these examples in the dictionary make it sound to me like there's a role reversal in Duolingo's classroom!
There's also fiafraigh for "ask", in the sense of "inquire" rather than of "request", but you can equally well use ceist a chur for that:
"To ask someone something, rud a fhiafraí de dhuine."
"To ask someone a question, ceist a chur ar dhuine."
Does "na daltaí" also mean "the pupils?" I reported "The pupils question the teacher."