Did anyone see the UFO's hovering over Opa Locka Elementary School around 1966-67?

This is more a plea for confirmation rather than an actual report to publish.  The reason I've decided to actually contact someone about this is that I have had memories of this incident that have haunted me for over 40 years that I was never quite sure was real or a dream.  That is, until I mentioned it to my father almost 10 years ago (he died in 1996) and he said it really happened.  I wanted to investigate it then, but was sidetracked.  
Then yesterday, my younger sister and I were discussing some childhood memories and she asked me, "What was that about ufo's at our school?"  I knew it was time to ask someone who could actually find information and probably others who remember this incident.
 It happened sometime between March 1966 and June 1967.  I was attending Opa Locka Elementary School in the northernmost part of Miami, Florida.  It was either the end of my 5th grade (66) or during the 6th grade (66-67).
This is the memory I have:  
Around noon, the police and alot of military (probably National Guard) came and evacuated the school.  There were alot of people standing around watching, but I just remember being escorted from the school because, (I saw this myself) 3 UFO's were hovering over the school yard.  It's funny that the actual UFO's are a blur to me, and the fact that we got to leave school early was the part that I remember being most excited about.  However, I remember seeing 3 objects, oblong but with 3 softly rounded sides shaped alot like a turnover, 1 long side with 2 shorter coming to a point in the center.  This was the shape from underneath not from the side.  They were metallic and very smooth and rounded.  I don't remember any sound coming from them.  There was one hovering over the Portable building, one over the woods just beside the school playgrounds, and one on the other side of the school.  I don't remember seeing that one, but for some reason, I know it was there.
Is there anyone out there that remembers this or has any information?  Pictures would be fabulous.  I can't imagine that it wasn't in the Miami Herald.  I have no way to find it myself.  I am also really curious to see how they explained this one.  If my memory is correct, they hovered there for most of the evening.  I don't know how long or anything about their departure.  I really don't remember them arriving.  Just seeing them there when were escorted from the school property.  And now that I know my sister also remembers, I want answers.  Please help if you can.
 The military doesn't evacuate schools due to weather balloons.
Date is approximate.  PD