The totally boring-b**ls**t physics/chemistry-demonstration kit for schools that was put out in the early '70's by Harcourt, Brace & World, Inc. The accompanying lesson-sheets were always irritatingly difficult to work with, and the company seemingly couldn't even spell "classroom" properly on the box's cover --- for years I had always thought it said "glassroom" because the bottom of the "C" and the top of the "L" were interlocked, and so it made da "C" look like a "G".... it was only when my fourth-grade teacher actually mentioned the name of the kit when speaking to another student that I finally realized what the label actually said!
Science class is spota be fun, but don't count on any happiness if your school relies on those insipid "Glassroom Laboratory" kits to teach da subject --- arduous and yuckyyyy...!!!