The story in three lines. For the Spring Fair, Captain Castle's academy re-stages the Immortal Game of 1851, in which White gives away a bishop, both rooks and the queen and still mates. Inkling keeps two columns in her notebook, MATERIAL and IN PLAY, and for most of the game they say opposite things. Warden Snare closes the queen's gates, Merle gathers everything in the wrong corner, Mason builds a wall across the queen's road home, Sir Sidetrack sends the last guard on an errand, and Kester finishes it.

One question to ask. "Black had far more pieces. Why did Black lose?" Then: "Can you think of a time when having more didn't help?"

One thing to do at the table. Play through the game, or just the last ten moves, and keep the two columns on paper as you go. At each stop, ask your child which column they believe.

The grown-up layer. The book teaches that material only matters if it can take part. Its Honest Page says plainly that the ending may never have been played on the board and that Black's eighteenth move was probably not the best. A fuller grown-up version is on the Whetstone as "Today's classic".