Student absentee rates remain a problem in spite of increased attention to absenteeism since the passing of the No Child Left Behind Act in 2002. High rates of absenteeism correlate to low academic achievement, early drop out, and increased risk of alcohol and drug abuse and criminal activity. This mixed method research design incorporated quantitative research to investigate the effect of a micro-level three-tiered positive behavior support program on decreasing absentee rates in elementary school classrooms, and qualitative teacher interviews to gain first hand contextual information regarding the implementation of the program. The research lasted 80 instructional days with the first 20 days establishing a baseline. The independent variable was the micro-level three-tiered positive behavior support program for decreasing absentee rates. The dependent variable was the absentee rate during the 60 day intervention phase. Four second grade classrooms were used for the research, each with a student population of 18, resulting in an initial sample size of 72 with a final sample size of 71 due to attrition. Two classrooms received a micro-level three-tiered positive behavior support program. The other two were used as a control. All teachers had similar backgrounds and experience and used curricula mandated by the district. Absentee data were collected daily through the Student Attendance Sheet and entered weekly into an Excel spreadsheet by the researcher. Descriptive statistics were used to analyze the data and a Friedman test was computed in STATLETS to determine statistical significance. Although the p value was found to be statistically insignificant at 0.47, there was a downward trend in unexcused absences for the treatment group. A semi-structured formal interview was conducted with teachers of the treatment group to gain information regarding teachers' perceptions of the intervention. Responses were coded for themes and findings revealed that while teachers agree positive reinforcement is an effective tool for shaping behaviors, parental attitudes and beliefs are central to decreasing absenteeism. Recommendations are that future research be conducted with a larger sample size and that a parent involvement component be included in the first level of the research paradigm. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]