This has been a really successful joint activity. Basically we have done repeated coats of paint on the box over 3 days (2 coats a day), and then when it was all dry we stuck on the wheels and photos. We used a really large masonry brush to paint with to cut down on time and maintain interest. The photos of the boys are them actually riding on a bus this week. Both boys visibly enjoyed all of this activity but especially the part where they stuck the photos on which was lovely to see.