Abstract
We report how experimental-type lectures for the local community are carried out in Gunma National College of Technology. While ordinary lectures for the local community have been held since 2002, we started the experimental-type lectures in 2004. In this paper, three experimental-type lectures for elementary schoolchildren are reported. The first theme is liquid nitrogen. Fruit and flowers can be frozen by the liquid nitrogen immediately because the temperature of the liquid is very low (ca.-200℃). An electric battery is the second theme. We let primary schoolchildren make the battery with fruit and charcoal. The familiar battery can turn a propeller. The third theme is rare-earth magnets. A so-called neodymium magnet, which is one of rare-earth magnets, is the strongest one among permanent magnets. With the neodymium magnet, mysterious experiments can be held.
