Phonetics is not a mandatory course in acquiring an English teachers' or elementary school teachers' license in Japan. Teachers without knowledge of or confidence in using phonetics are likely to use Katakana in teaching pronunciation, which leads to unintelligible pronunciation. Based on the consideration that IPA is the solution, an experimental lesson was given to junior high school students using newly devised teaching materials. The experimental group which was taught IPA by a teacher without knowledge of phonetics, proved to be significantly superior to the control group in the pronunciation test.
