This Monograph reports a follow-up investigation of children whose early use of television was evaluated at age 5. The follow-up took place more than a decade later when they were in high school. Early viewing of educational and informative TV was related to higher high school grades in English, Science, and Math. Differences in intelligence, parental education, income, or birth order were not causal. The benefit of early educational viewing for later years was stronger for boys than for girls. The opposite was true of the negative impact of early exposure to entertainment cartoons. It was harmful for girls, but not a bad for boys. The medium of television is not homogeneous in its impact on children. Instead, it depends on what they watch and whether they are more vulnerable to neglecting the good programming (boys), or to watching the bad programming (girls), just before their first experience with schooling begins.