Sometimes being proactive in planning, can prevent problems. Recently an inter-generational group of friends and family gathered to build a deck and ramp to assist an an older couple with accessibility to their home.
In advance, the process of working together and involving everyone was established as being as important as finishing the project. Children and adults without skills would be taught them by those who had the skills. Little ones who participated for awhile but then lost interest could be involved in something else.
Children as young as 4 and adult men and women who'd never used a saw, a level, a jig, or screw gun in their life helped. They learned quickly. The experience built confidence and made both children and adults feel empowered. 3 cheers go to the expert builders (Joe, and Mike, and Fred) among us who caught the spirit and taught patiently. Safety was taught and modelled too (You don't see the safety glasses, gloves, and other equipment in the pictures but they were there and they were used.)
The kids helped and played and helped and played in spurts but also learned skills and saw amazing adult modeling! There was little whining for attention because they were involved.
Sometimes it might seem easier and faster to not involve everyone but it is less beneficial in the long run.