After 18 months of distance learning, the hallways of McClymonds High School in Oakland were once again filled with students laughing and chatting as they went from one class to another.
For geometry teacher Floresa Vaughan, it was a scene she missed after a year of teaching online.
"It seems more chaotic, but it's a chaos we know how to handle," said Vaughan, who leaned against the door of her classroom and just watched students pass by.
"Even though you can't see the smiles, you can hear them and you can feel them," said Vaughan.
A few former students stopped to say hello, but she only recognized them when they said their name, a consequence of teaching to students who did not have to turn their cameras on for an entire year.
COVID-19 has made the first week of school more anxious than normal. Principal Jeffrey Taylor estimates more than half of the students don't know their way around the school.
VIDEO: A look back at the start of distance learning last year
"Our ninth graders have never been on campus and then our 10th graders, who were 9th graders last year, have never been on campus," said Taylor.
Sophomore Raniyah Cole knows the feeling.
"It feels like I'm a freshman. It doesn't feel like I'm a sophomore," said Cole as she waited for her first in-person class at McClymonds.
Even though the pandemic changed the lives of teachers and students, there was little talk about the coronavirus during class time except to remind students to keep their masks over their mouths and nose.
"We don't want an outbreak at this school so we are constantly reminding our students to pull your mask up," said compliance specialist Alberta Smith, who spent the morning making sure students had their correct schedule.
Smith said the school has a protocol to follow if a student feels ill. They are sent home with a self-test kit and if their test result is negative, they are allowed to return to campus. If the test result comes back positive, then the school will do contact tracing to notify students and staff who may have come in contact with the infected student.
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McClymonds High School is located in West Oakland, which has one of the lowest vaccination rates in Alameda County. According to the public health department, the area had a transmission rate of nearly 900 infections per 100,000 people during July.
"These kids are going to homes where the adults are not vaccinated, which puts a lot of us at risk," explained Vice Principal Renee Bullie. "It is very important that they protect themselves and us as well."
Despite the rising transmission rates from the Delta variant, the school year began without a vaccination mandate from the Oakland Unified School District. That changed the next day.
By Tuesday evening, OUSD decided to require all staff, contractors and volunteers to get vaccinated by September 7. Those who don't get vaccinated will be required to get a COVID-19 test at least once a week.
Family advocate Tolani King is one of the staff members who worries about the rising infection rates.
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She understands the district can't mandate students get vaccinated, but she wishes there was a way to test them regularly for the coronavirus, especially since students are allowed to sit close together because the district did not implement social distancing requirements.
"These kids are used to being home without wearing a mask so now that we are asking them to keep it on they feel it irritates them. We need to do more education about the importance of masks," said King.
The lack of social distancing also worries head football coach Michael Peters, whose players get tested twice a week.
"The rest of the school doesn't test like we test so it's going to be challenging. I am making sure my guys keep their masks on when they are with other students so we stay as safe as possible," said Peters, who fears the football season may be suspended if there is an outbreak among players.
That's something that has senior Isaiah Smiley worried as well.
"I am anxious about everything shutting back down because then I will lose out on the whole senior year," said Smiley. He saw how the players who graduated last year had a hard time getting recruited because the season was delayed until March.
The directive from the school district does require students to keep their masks on even when they are outside, including break periods and lunchtime.
Biology teacher Angelique Jacques-Marcoulis described the week as a roller coaster of emotions.
She waited to be vaccinated until the district announced in-person instruction would resume. Still, she was unsure about a vaccine mandate on the first day of school, but by midweek, when the district announced the new requirement, she understood why it was needed.
"We can get ourselves vaccinated to keep ourselves safe. We already found out what happens if teachers don't come to school. We shut the world down," said Jacques-Marcoulis.