"Yes, there are students here."
Translation:Так, тут є студенти.
This is somewhat a mystery to me as well, however I asked a Russian speaker who knows some things about Ukrainian and he said that the word order is almost always Subject-Verb-Object like in English, so є - being a verb - would probably have to come before студенти assuming that студенти is not the subject i.e. "There are students here."/"Here, there are students." as opposed to "Students are here" which I believe would be translated as "студенти тут".
Interestingly, though this may be in error, DL doesn't accept "так є студенти тут" but instead states that "так, тут є студенти" is the correct solution which may indicate that "тут" in this sentence is an adverb to "є" which must precede the verb. I'd really like if a native speaker could comment on this as at this point we're just beginning to learn the sentence structure and we haven't much of a guide to what's considered proper.