Classroom Technology in the early '80's

The only technology I remember regularly being used in my middle school classroom was the overhead projector. Teachers would write notes or work out math problems on a clear sheet of plastic with erasable colored pens. When the plastic sheet was placed on the bright base of the machine, the information would be projected to the screen in front of the room . Even with this low level technology, there were times the light bulb had burned out and the teacher had to scramble to adjust the lesson plan. Most of my teachers used chalk and a chalk board for communicating information.