Lobby the college/town/city/county/state (depending on whose road or sidewalk is in question) to ammend their signage and road markings, where it makes sense.

Maybe the road where you got stopped (or the alley another poster mentioned) could accommodate two-way bike traffic, with the current one-way car traffic.

If there's a student group that could lobby the college (bike club, or whoever), they might gladly change that road.

For the alley--I would guess it's either a town/city street, or maybe a private street with a public right-of-way (some alleys are that way, in some places). You could start making calls, or get a student group involved, or maybe someone more "official" and the collee might want to get involved, in the name of student safety. It might be a bigger problem for a municipal street, since they might have to do things like commission a traffic engineer's study, which can make it end up costing much more than the price of a few signs and a couple buckets of paint.