Small learning communities

A Small Learning Community (SLC), also referred to as a School-Within-A-School, is a school organizational model that is an increasingly common form of learning environment in American secondary schools to subdivide large school populations into smaller, autonomous groups of students and teachers. SLCs can also be physical learning spaces.

The primary purpose of restructuring secondary schools into SLCs is to create a more personalized learning environment to better meet the needs of students. Each community will often share the same teachers and student members from grade to grade. Teachers in these units usually have common planning time to allow them to develop interdisciplinary projects and keep up with the progress of their shared students.

SLCs can take several forms.

...
Wikipedia