Our family has transitioned through a Chariot trailer, Adams Trail-a-bike, short Yokota mountain tandem (16.5" - 14") to a Kuwahara road tandem (22.5"- 22.5"), as legs and distances grew longer. Each step was to a smoother, more stable ride, and both our kids (now 14 and 8) have learned city bike safety and riding techniques with easy and fun riding conversations. Find a cheap used 26" wheel tandem and see if it fits your family. My 14-year-old daughter's response to every suggestion of a ride is, "I am not going, unless we take the tandem".

-Will