Two cups in a pint, two pints in a quart, four quarts in a gallon. These free printable sheets convert between the customary measures of capacity — the ladder children mix up because three of its steps are doubling and the last is not.
If they get stuck
The answer key prints on a separate page.
The trap in this ladder is that it looks regular and is not: cups to pints doubles, pints to quarts doubles, and then quarts to gallons multiplies by four. A child who assumes doubling all the way turns 4 quarts into 8 instead of into a gallon. Each question is a single step so the one factor in play is clear, and the steps are drilled where the child keeps mixing them.
Going to a smaller unit multiplies, to a larger unit divides, and both directions appear on every page. Amounts stay whole or half so the reasoning is which factor and which direction, not the arithmetic — and the estimate at the end catches the doubling mistake when it happens.
One question from a sheet like this one, worked a step at a time — with a sentence saying what just happened and why.
Customary capacity conversion, step by step