Why this matters
NCES pupil:teacher ratio is enrollment ÷ full-time-equivalent teaching staff. It isn't class size — specialists, resource teachers and coaches pull the ratio down without changing what's happening in a classroom — but a lower ratio generally means more adult attention per student.
What we're seeing
At Columbia, the student:teacher ratio has risen 6% over the 5-year window — from 16.1:1 in 2020 to 17.0:1 in 2024. Despite that, the gap vs US average of 15.4:1 has actually widened — from 0.7:1 above in 2020 to 1.6:1 above in 2024.