"A long time ago, there was no such thing as school, and children spent their days learning a trade, a phrase which here means "standing around doing… - Daniel Handler

"A long time ago, there was no such thing as school, and children spent their days learning a trade, a phrase which here means "standing around doing tedious tasks under the instruction of a bossy adult." In time, however, people realized that the children could be allowed to sit, and the first school was invented."