School reform efforts aimed at promoting equity and excellence at urban school settings are heavily dependent upon the quality of teaching personnel that are used to deliver the instructional program. Social Justice and other public policy issues related to equity and excellence at urban schools have begun to examine the impact that teacher absenteeism, and by extension the reliance on substitute teachers to deliver instructional might have on educational attainment. This study combines school district data gathering mechanisms on teacher absence rates at school sites with Geographical Information Systems (G.I.S.) to map the association between a school's geographical environmental space and the propensity for teacher absence. The disparity between teaching resources as delivered by the school district vs. teacher resources as actually received by students in the classroom via teacher absenteeism is examined in the context of schools located in positive (high income) and negative (low income) geographical space. The study concludes that there is a strong association between the geographical quality of the school site setting, teacher absenteeism, and the reliance on substitute teachers to deliver instructional programs. Disparity in teacher absenteeism rates across large urban geographical areas threatens the promotion of equity and excellence in the schools by attenuating or lessening the effect of school resources to support instruction and amplifying the risk factors of students in the classroom.