The number represents almost 20% of the student body there.
The students sent home were asked to quarantine at home for 10 days.
Roughly 20 people at the high school have tested positive for COVID-19.
Throughout the Lake Elsinore Unified School District, a total of 500 students at seven schools have been sent home due to possible exposure.
Lake Elsinore USD notified parents on Tuesday about the impacted students. The district told Eyewitness News that officials implemented contact tracing, but because the students are still very new to the school, they had a hard time identifying close contacts.
Out of an abundance of caution, school officials sent those 300 students home to quarantine for the next 10 days and to monitor themselves for symptoms.
A handful of parents arrived on campus Thursday to pull their kids out of class. The district said these parents did so based on their own needs as a family and their own health concerns.
Some expressed concern over the number of cases, especially since school just started.
"Three-hundred is a lot. Imagine next week or the week after that, there's going to be more," said Bryana Ledesma of Lake Elsinore.
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