What can I call other students if I am also a student?

You could use peers. This is potentially ambiguous, but depending on the context, it may be obvious to the listener who you mean by peers.

A schoolmate:

A person who attended school with the subject.

Fellow students is also correct and grammatical.

At my university, professors usually refer to other students as our colleagues and encourage us to do so during presentations and talks.

You might consider cohort:

An assistant, colleague, accomplice.

or

A company, band; esp. of persons united in defence of a common cause.

If you wanted a word that expresses solidarity as students, this might be a good choice. When I was in grad school, we used it to refer to those of us who matriculated the same year; it provided a nice sense of unity in the face of adversity (a heavy workload!).