Geeks in their late 30's or early 40's might remember this video from elementary school in the mid-to late 1970's. It's called "Telezonia," and was produced by AT&T (which some of us remember as "Ma Bell," "The Bell System," or just "The Phone Company").
It was meant to teach elementary school students about using and understanding the telephone. I remember watching this in 2nd grade in 1977. I know it seems hoplessly dated, but even if you're too young to remember it, it's kind of interesting to look back a few decades at the technology of the time.
Fair warning: It's just under 30 minutes long, so if you don't want to be stuck on my page watching this, here's the link for Telezonia at Google Video so you can bookmark it/watch it later.