I am a bit unclear about what you are asking, so I'm going to try to cover all the possibilities below -- hopefully, one give you the answer you seek.
Otherwise perhaps reading some of this website will help:
PhotoTherapy techniques are "therapy practices" (work done by licensed therapists and counselors) and so the person doing them must be already trained and certified as a mental health professional first, before using them with their clients.
This training requires university graduate-school level education and so no, students in junior high cannot DO PhotoTherapy. To do PhotoTherapy, you need to be counseling someone else -- and it is what you "do" while you are helping them that defines this process as being "PhotoTHERAPY"....
HOWEVER: People who want to help those students -- for example, school counselors, social workers, psychologists or even psychiatrists -- CAN use PhotoTherapy techniques to help the students with problems and family difficulties...
The other "half" of this field is "Therapeutic Photography" -- and that IS possible for students to do for themselves, because Therapeutic Photography involves photographic activities (photo-taking, photo-viewing, photo-changing, photo-sharing or discussing, posing for your own photos (or someone else's), your family photos, and also what is done WITH the photos (put into albums, share online, tell stories about, and so forth).
People using "Therapeutic Photography" techniques can be anybody -- and so yes, students (of any age, even elementary school!) can DO Therapeutic Photography -- but to do PhotoTherapy, you need to have post-graduate University training.
I hope you got your answer?? If not, please explore the website and I think it will answer better.
Judy Weiser, R.Psych., A.T.R., Director of the PhotoTherapy Centre
PhotoTherapy and Therapeutic Photography website