If you own a student ticket at the Bonn or Cologne University, you also obtained a ticket for traveling the region with the public transport. Not only Bonn and Cologne can be visited with that ticket, but numerous other interesting places all over the region.
Radiotelescope in Effelsberg (more infos) (open tuesday to saturday from 10 am to 5 pm)
Bad Honnef (nice living at the Rhine)
Coal at Garzweiler (forced translocation)
Leverkusen (chemical industry)
Bergisch Gladbach (paper industry)
Bad Münstereifel (oldtown)
Anfahrtinfos unter: VRS-INFO