The local high school district is seeing an increase in COVID-19 cases in the last week. Officials are chalking up the rise to a combination of exposure over spring break and a general rise in cases throughout San Mateo County.

The around 10,000-student Sequoia Union High School District reported 102 cases last week, made up of 90 students and 12 staff members last week. Of those, 15 were at Menlo-Atherton High School in Atherton, 11 were at Woodside High School and two were at TIDE Academy in Menlo Park.

Although this is a higher number than preceding weeks, it is still far from the surge of cases — 710 in one week — that followed winter break in January.

Students and teachers were on spring break the week of March 28. The week of April 25 there were 53 cases. The week before that, there were 46 cases.

The average daily case count in the county has increased 18% over the last two weeks, according to data from The New York Times. There were an average of 315 cases per day as of Wednesday, May 11.

The district, like many others in the state, lifted its indoor mask mandate in March. It still strongly recommends students and staff wear masks on campuses.

The district hasn’t seen any evidence of on-campus spread at this time, according to Superintendent Darnise R. Williams.

When asked if masks could come back on at district schools, Williams said officials will continue to closely monitor the situation and will rely on guidance from the county health department.

“At this moment, the circumstances have not called for any changes to our protocols,” she said.

Menlo School, a private school in Atherton, reinstated its masking mandate on April 27 because of an increase in cases after spring break, according to an email to the school community. Starting Monday, May 9, masks were “highly recommended” on campus, the email states.

Elementary school districts aren’t seeing the same increase in cases.

The around 2,700-student Menlo Park City School District reported 18 cases last week. Case counts have stayed around 20 cases per week since the district’s return from spring break, which was the week of March 28. Cases were in the single digits in the two weeks before spring break.

There were four cases of COVID reported from April 23 to 29 in the 1,500-student Ravenswood City School District, which has schools in East Palo Alto and Menlo Park. (The district’s count only includes students and staff who were on campus during their infectious period.)

Ravenswood is the only district locally that still requires students and staff to wear masks in classrooms.

The Las Lomitas Elementary School District, which has about 1,100 students enrolled at schools in Menlo Park and Atherton, saw 12 cases last week and 10 the week before.

The around 477-student Portola Valley School District reported six cases last week, but saw a small spike the week of April 11 (about a week after students returned from spring break).

The Woodside Elementary School District, which has about 360 students, reported three cases last week.

The district sent each student home with a COVID-19 test before heading off to spring break to test before returning to school on April 18.