Helping kids learn to share

One mom reported that she and her husband had gone shopping with their two children. They purchased a scooter for their 4-year-old daughter and a large toy plane for their 2-year-old son. Both children were happy with their selections at the store. However, when they got home her son also wanted to be able to ride the scooter.

Since both children wanted to use the scooter at the same time, Mom helped them figure out how they could take turns. Although she taught them to use a timer to keep track of how long each child had, her daughter sometimes “helped” the timer along when it was her brother’s turn. He then protested that his turn was too short.

Mom got tired of the arguing and approached her husband about buying another scooter to fix the problem. Her husband thought this would only be a temporary fix and that the children really needed to learn to share. How would you have handled this situation?