SAN FRANCISCO (CBS SF) — Fearing staff shortages when their classrooms reopen in April, San Francisco school officials sent out notices Tuesday to more than 2,000 full-time teachers with their reopening assignments and launched a search to sign up additional substitutes who will be needed.

The school district was preparing to gradually return students to in-person learning from the first time in over a year beginning on April 12.

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San Francisco Unified School District officials have sent out 2,085 assignment letters to teachers and paraeducators who are being asked to return to in-person learning in the first three waves of schools.

PK-5 teachers and paraeducators who are at “increased risk for severe illness from COVID-19 or who cannot safely distance from household contacts who belong to a group at increased risk” can request an accommodation to work remotely this spring.

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“Given early indications that there may be a shortage of staff who are able to work in person at this time, the district is surveying substitute teachers about their availability and working to recruit and hire additional substitutes,” officials said in a statement.

The district is also hiring for substitute teachers who are interested in distance learning assignments, as well as one off in-person substitute positions.

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People may apply to become part of SFUSD’s on-call substitute pool at any time.