How would I conduct a paranormal investigation at my school?

I have many reasons to believe my school is haunted, me, my friends, and my janitor, and my mother have all had encounters that were quite freaky. Me and my friend decided to see if we could but we do not know how and we do not have equipment for a professional investigation so we are going with an iPod 4, our phones, flashlights, and 2 video cameras. So will this be enough to catch anything? We figure yes because we can hear and see stuff with the naked eye and ear. Also would I have to just clear it with the principal?