This study investigated the impact of the years of teaching experience of classroom teachers on the achievement of third-grade students in inner-city Title I Schools; on the achievement of those third-grade students who were defined as high achievers, average achievers, and low achievers; and on the achievement of boys and girls in the third grade of inner-city Title I schools. An analysis and interpretation of the data revealed that there were no significant differences in reading and mathematics achievement of the third-grade students when the number of years of experience of the teacher was examined. Reading achievement of third-grade boys and third-grade girls did show significant differences. The more-experienced teacher appeared to have the greater increase in reading scores of the students. In addition to data concerning the hypotheses, information about other teacher variables was collected through a teacher self-report questionnaire. One hundred per cent of the teachers in the participating schools responded to the questionnaire. Data were tabulated by frequency of response in groups according to years of teacher experience. Variables included years of teaching experience in Title I schools, classroom size, and demographic data. Analysis of the data indicated that teachers having more years of experience in Title I schools appeared to have a greater increase in the reading and mathematics scores of students. Students in larger classes appeared to show greater gains than students in smaller classes in reading and mathematics. The majority of the teachers indicated that they felt the teacher, parent involvement, and class size had the most impact on achievement of students and staff development had the least impact.