One basic role of teachers in education is to promote academic performance. The success or otherwise depends solely on the many aspects which the school revolve, being in charge of daily running of the school academically. Schools can make a difference to students` performance and the teachers` input is one factor determining that success, hence it is important that the performance of a school is appraised against the performance of the teacher and vice versa. This book employs descriptive survey, the study population comprised 1650 respondents comprising 150 school principals and 1500 students drawn equally from the two areas, Multi stage stratified and simple random sampling techniques. Data collected were analyzed using frequency counts, percentage, means and Pearson Product Moment Correlation. Five null-hypotheses were tested at 0.05 level of significance. The study reveals that the input of Youth teachers on secondary school students was close in the two distinct areas in Kenya and Nigeria and, as such students` academic performance was significantly related to teachers` Work Habit, General Ability, Resourcefulness, Personal Qualities and Mental Stability.