The purpose of this study was to investigate the initial one-year effects and the second-year follow-up effects of introducing programmed English as a Second Language into the elementary curriculum. The initial phase or Phase I was concerned with determining the effect of English as a Second Language (ESOL) on the achievement of first year elementary students. The follow-up study phase was designed to determine the extent of any residual effects on the achievement of second, third, and fourth grade students receiving the programmed ESOL instruction during the academic year just preceding the year considered by this report. Achievement areas involved were reading vocabulary, reading comprehension, total reading scores, mathematical reasoning, math fundamentals, and total mathematics scores. The subjects were students from culturally disadvantaged Negro homes enrolled in the Laboratory School on the campus of the Mississippi Valley State College. It was found that no valid judgement could be rendered regarding the effectiveness or non-effectiveness of the programmed ESOL materials used. Due to the contamination of the control group, no true analysis was possible. More than one year of ESOL would be needed to determine the permanent effects, if any, on the achievement of the students. (DO)