Globe at Night is a worldwide campaign to raise public awareness of light pollution.  Several campaigns are held during the year. The idea is simple - how many stars are visible from your location?  Between 8pm and 10pm local time, go outside and look at a particular constellation, then match your observation to one of the star charts on the Globe at Night website. The constellations used are Orion, Leo, or Crux, depending on your location and the time of year. This can be done as an individual, or as a classroom project. In 2012, observers from 92 countries contributed 16,850 observations, giving an idea of where light pollution is the worst, and where the sky is the darkest. Details can be found on the Night Sky Network website.