What is "jotters"

Usage examples of "jotters".

I found some interesting things while I was doing all this: a home-made astrolabe I'd carved, a box containing the folded-flat parts for a scale model of the defences around Byzantium, the remains of my collection of telegraph-pole insulators, and some old jotters from when my father was teaching me French.

I'd bought real stave paper from a music shop, carefully transcribed all the quavers and hemi-demi-semiquavers from my old exercise jotters, and then typed in the words underneath.