Class C4 at Coal Hill School was taught by Barbara Chesterton in 1963; she taught history. It was the smallest of the history venues, and close enough to Ian Chesterton's lab next door to smell the stench.
In one session, Barbara taught about the Corn Laws. (PROSE: Nothing at the End of the Lane) Among the class's students was Susan Foreman, who handed in a paper regarding decimal currency. Susan later asked to borrow The French Revolution, a book on the French Revolution. Barbara found this curious, and shared this information with her colleague Ian, the science teacher of Class C3. (TV: "An Unearthly Child", PROSE: Nothing at the End of the Lane)