This study was conducted to determine if using heart monitors to measure exercise intensity in a physical education class would effect PACER scores and VO2max. The variables of the PACER scores and VO2max scores were measured at week 1 and week 8 of a fitness program developed by the Cooper Institute for Aerobics Research (CIAR), Dallas, TX to determine any significant differences. Ninety-nine junior high subjects from a middle school in Sacramento, California ages (11-13 years old), participated in the eight-week study. Analysis of the pre/post PACER scores between the control group, PF group, and PF/HRM group revealed no significant increases. Analysis of the pre/post VO2 maximum scores between the control group, PF group, and PF/HRM group revealed no significant increases. A secondary analysis was carried out on subjects in the control (n=19), PF group (n=12), and PF/HRM group (n=18) who reached stages 4 and 5 of the PACER test to equate pre-PACER mean scores. Significant differences were revealed in pre/post PACER scores for the PF/HRM (stages 4 & 5) group (p £ .05). The PACER scores of the PF/HRM group increased significantly from the pre-test to the post-test. This study revealed the students who reached Stage 4 & 5 in the PF/HRM group showed significant improvement in PACER scores. The current study gathers statistical data to validate using heart rate monitors in physical education classes. A longitudinal study using heart rate monitors to measure intensity levels in students, that is greater than an eight week period is recommended to provide more conclusive in changes in PACER and VO2max scores.Keyword(s): assessment