This is a real school tablet, Mesopotamian, somewhere between the 20th and 16th centuries B.C. according to the museum. A student copying signs. You can see where the stylus pressed.

Cuneiform is the oldest writing system we know of. It started in Sumer and stayed in use for an absurdly long time; the latest tablet that can be dated is from around AD 79/80.

Wedges into clay. People learned it by copying it over and over, which is still how most of us learn most things.