Some students told ABC7 News they were feeling a little cautious after Monday's threat. "Coming back to school feels kind of scary. None of us thought this would happen here and now it has happened, it's odd it's happening," sophomore Esteban Duran said.
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Police said the threat wasn't credible and that it was an online challenge to see how many schools would cancel classes.
More than 50 Bay Area school districts received a threatening email, many of them were just coming back from spring break Monday morning.
Emeryville did cancel classes Monday and some parents had a hard time bringing their children back to school on Tuesday.
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Other parents told ABC7 News they discussed the threat with their kids and showed them news coverage to reassure them that the threat wasn't real.
The FBI said the hoax was sent to schools in at least 46 states.
While things appeared to look normal outside of Emery High Tuesday, Superintendent John Rubio has not returned calls or emails to ABC7 News.
Below are the local school districts that ABC7 News confirmed were affected:
Alameda County School Districts:
Officials say at least 13 of the 18 Alameda County School Districts received the email on Monday. All immediately reached out to local law enforcement.
San Mateo County:
The county confirms that the San Mateo County Office of Education, the county superintendent and Cabrillo Unified School District received hoax emails Monday morning. They say that is only one district of 23 in the county, and about half the schools are on spring break and operations were not disturbed there.
Contra Costa County:
The county says at least nine of the 19 districts received a hoax threat email. Parents were contacted by all districts.
Officials did not give a specific number, but the Office of Education says that "many" of the 40 school districts in the county were threatened. They provided more information here.
Oakland Unified School District:
The school district says they received at least one of these emails but it did not disrupt normal school operations.
San Ramon Valley Unified School District:
Brentwood Unified School District:
Click here for more stories related to school threats.
ABC7 News' Kate Larsen contributed to this report.