All students attending Griebling Elementary School in Howell will be remote for the next three days as county health officials work on contact tracing.
It is not clear if the positive case is a student or a staff member.
Meanwhile, Frankford Township School District is switching to remote learning for two days after a student tested positive.
It's also the first day of school in Hoboken, where all students across the district will be learning remotely for now.
The district will take this week to welcome students and their parents, and invite them to prepare for in-person learning.
That includes classroom and safety walkthroughs.
Students whose families choose in-person learning will be back in school next Monday.
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