Current Californian high school math classrooms may have sizes of 1 teacher to 40 students, with classroom size penalties ending at middle school. This is also true of the more prestigious areas mentioned in this forum. I cannot imagine a successful Montessori experience with 1:40 ratios.
When considering the issue of individual variability in math ambition and readiness, it's more plausible to have a student who is ready for Geometry to move into a classroom where a teacher has already been polishing a year-long discourse on Geometry, as opposed to expecting any teacher to be ready for a discussion on Geometry.
Under Equitable Math this will not be possible. Instead, all students must always be at the same level up until the last year.
When considering the issue of individual variability in math ambition and readiness, it's more plausible to have a student who is ready for Geometry to move into a classroom where a teacher has already been polishing a year-long discourse on Geometry, as opposed to expecting any teacher to be ready for a discussion on Geometry.
Under Equitable Math this will not be possible. Instead, all students must always be at the same level up until the last year.