My friend and I were trick or treating along our neighborhood route which took us past our school.  The school being located on the north side of the street and homes on the south side.  The school takes up the entire block and has a large athletic field that sits on the west end of the school and behind the school are railroad tracks. We had just finished that street turned south at the end of the block and then turned east at the next block.  At this point we had not noticed anything. Then as we were walking up to the 2nd house on the block we noticed this HUGE!! disc-shaped object with lights of different basic colors spinning around the disc. As it started to clear the house tops and we realized the size, bigger than the house we were walking up to, we were horrified.  My friend ran up under the carport; I was too afraid the owners would find us and be mad so I stayed out about 15secs more until it cleared the house tops & starting moving slightly and very! slowly south scaring me enough to the carport.  Still scared between the owners or disc, I ran back out from under the carport just in time to see it hovering basically above us.  It was astonishing, massive, and the lights were mesmerizing.  I can't remember if there was any sound associated with it.  Then once it cleared the trees; it shot into space and was gone. We were both horrified and decided it was a Halloween prank.  Neither one of us ever mentioned it again to anybody or even to each other. There is no way in 1975 anyone could put together something of this magnitude.