Just north of Copenhagen in the suburb of Hellerup is Experimentarium City, a hands-on science museum that's mostly for children but just as fun for adults. Exhibits include an investigation of the human body, a sound wave lab, gyroscope, and robot programming display. It's a little bit out of the way, but is an educational way to wear out energetic kids, and is reachable by public transportation. Admission is 160 DKK, under-2s are free.