I agree that it's reasonable for teachers to not want to do more work. And I understand that creating tracks will separate students — but that doesn't require creating the perverse incentives you describe.
Teachers can simply be evaluated based on how their students do, relative to the students' prior performance. This wasn't a problem before 2014, when CA made GATE optional. Everyone understood that different teachers had different cohorts with different average abilities.
The teachers with lower-performing students weren't dinged because their students scored lower than the students in advanced classes. Instead, teachers could specialize in remedial, typical, or advanced learning.
Teachers can simply be evaluated based on how their students do, relative to the students' prior performance. This wasn't a problem before 2014, when CA made GATE optional. Everyone understood that different teachers had different cohorts with different average abilities.
The teachers with lower-performing students weren't dinged because their students scored lower than the students in advanced classes. Instead, teachers could specialize in remedial, typical, or advanced learning.