DELAWARE COUNTY, Pa. (CBS) — As of Tuesday, all students in the Chester Upland School District can return to school buildings, at least part of the time. Eyewitness News was outside Chester High School.

This was the first day that grades three through 12 could begin hybrid learning.

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Pre-k through second graders transitioned to hybrid learning last month.

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Students are divided into two cohorts and report to schools on different days.

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About 900 students district-wide are returning in person while 1,700 will continue full remote learning.