Review on Invisible Classroom: The Ultimate Christmas, Thanksgiving, and Halloween Experience by Eric Mueller

Our group of 7-12 year olds loved it! We bought these as gifts for the glow party and they were a hit. Wow, they work on both skin and paper, so girls have been using them to draw invisible messages and do their own makeup! All the pens in the set worked. The lights work very well (and were also used all night to recharge the girls' glowing nail polish). The felt tips didn't seem to have very wet or heavily charged ink, and I would expect them to dry fairly quickly. But for our purposes, these pens were fantastic.