(CNN)High school teacher Sarah Giddings stayed home again Friday after more online threats and jittery nerves forced her school and others in southeast Michigan to close.
Giddings, 39, comes from a family of educators who -- along with school staff, students and their parents across the nation -- have become unwilling participants in a recurring American nightmare.
The copycat threats have been rising since Tuesday's shootings at Oxford High School, according to CNN affiliates WJRT and WXYZ. A 15-year-old sophomore is accused of fatally shooting four students in the halls of the Oakland County school -- about an hour from where Giddings teaches English and social studies.
It was the deadliest at a US K-12 campus since 2018 and the 32nd school shooting since August 1, according to a CNN tally.