As many schools move toward serving a broad range of students in heter
ogeneous settings, it is important to assist teachers in developing cl
assrooms responsive to the needs of academically diverse learners. Und
erstanding what impedes and what facilitates appropriately differentia
ted instruction is essential for educational leaders if schools are to
move away from one-size-fits-all teaching and if heterogeneous classr
ooms are to become viable for ''academic outliers'' such as gifted, st
ruggling, and special education learners. This case study examines the
experience of one middle school confronted with a district mandate fo
r differentiated instruction and presents the factors which impeded or
facilitated their movement toward appropriately differentiated classr
ooms.