This study aimed at an investigation of four television teaching techniques via a closed circuit system. Eighty vocational agriculture students comprised four groups: group A viewed the program without any opportunity to participate in two way communications or ask questions before or after the telecast; group B viewed the program as group A but had a group leader qualified to answer questions concerning subject matter; group C viewed the program as group A and, in addition, had two-way communication with the television instructor via telephone (they had no group leader); group D viewed the program as group B and in addition to a group leader, had two-way communication with the television instructor in the studio. An analysis of variance showed no significant overall effect due to the treatments and a multiple range test showed a significant difference only between the extremely high and the extremely low means -- no teacher/with phone being significantly lower than teacher without phone. (author/nl)