By Joe Holden

UPPER DARBY TOWNSHIP, Pa. (CBS) — While some school districts in the Philadelphia region have struggled to offer any in-person learning, Catholic schools have stayed open throughout the pandemic. Joe Holden takes a look at what’s working for them, and why.

Mr. Pederson’s seventh-grade class at Saint Laurence was just wrapping up a lesson on women in aviation when we dropped in.

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Unlike the full-scale reopening debate happening in public school districts, the Philadelphia Archdiocese Catholic School system has been up and running five-days-a-week, in-person since September.

And they’re proud of it.

“We did it. I didn’t think that we would be able to do it but we have done it. We have done what we thought was impossible,” said Saint Laurence Elementary School Principal Sister MaryAnne Bolger, IHM.

Eighth-grade teacher Patricia McPeak says she is proud of how this Upper Darby Township parochial school navigated full-time school in a pandemic, saying they never missed a beat.

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“We missed major events like our Christmas pageant, we missed socializing. But this cohort thing seems to work because this is where we are from 7:30 until 2:30 — lunch, recess, they’re in their room,” McPeak said.

When a Catholic school would have a suspected COVID case, that class or cohort would migrate to virtual learning. Other parochial schools delayed in-person learning around popular travel holidays.

Archdiocesan Superintendent Dr. Andrew McLaughlin says separating students into cohorts was key.

“That allowed us, if there was a child who caught COVID, then we just had to try to do the tracing within that group and we didn’t have to shut the whole school down,” McLaughlin said.

Another Catholic school in Ridley Park called the full-time effort “colossal.”

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Budget-toppers for most of these schools have been cleaning supplies, and they do add, they have seen a slight enrollment bump because they are back full-time.