So my daughter's Girl Scout troop is selling cookies, and they are collecting boxes for local servicemen with a goal of 80 boxes. They want a thermometer style sign to show their progress. Something easy to set up, free standing, about 3' tall, yet still small enough to fit in a car trunk.

My original thought was to use a 2x4 for the vertical, cut a square notch on both ends, with a dowel spanning the notch. On one face will be a plexiglass plate painted to show the shape of the thermometer with graduations. For the indication, I planned on making a loop out of wide ribbon, half red, half white, and tension it across the dowels so they can slide it up/down as necessary.

Then I got the idea of incorporating a crank, so that means gears and springs and a belt etc...unless one of you guys have a better idea. I'm pretty handy, and have more tools than the average bear. Anybody got anything?