I'm still rehashing the walking, biking fund raising ideas and it appears cheap pedometers are available so every walking participant could register miles. Is there a cheap thingy that records miles for a bike?? I know there are expensive pieces of equipment but just wondered if there is something cheap that can get attached and detached to a wheel, for instance??? DDD by the way I put "photo scavenger hunt" in for a google search and it appears they are quite common. I couldn't find an actual description of specific planning in all the hits but I suppose common sense and a little imagination might work.