1, provide a reference for ducklings: Ducks are not in a line. You can provide a reference for ducklings to help them align, such as drawing a line on the ground or putting some pebbles to align them.
2. Provide a leading duck for the ducklings: You can choose a duckling as the leading duck and let other ducklings line up.
3. Give some rewards to the ducklings: You can give some rewards to the ducklings, encourage them to queue up, and give some biscuits or toys. This will give the ducklings more motivation to queue up.