The cause for the decrease can't be determined, as some districts went to remote learning or shut down classes entirely ahead of the long weekend.
Cypress-Fairbanks ISD had one of the biggest increases in cases overnight, with more than 1,000 total active cases for the first time this school year.
However, compared to its overall enrollment, the district has only nine cases per 1,000 students.
Sweeny, Columbia-Brazoria, New Waverly and Tomball school districts have the most cases per students enrolled with at least 30 cases per 1,000 students.
Although only 1,844 students are enrolled for in-person learning at Sweeny ISD, the district has the highest number of cases in the Houston-area region based on its enrollment with 80 active cases among students and 16 active cases among staff as of Wednesday afternoon.
13 Investigates is tracking COVID-19 cases at dozens of districts across the Houston area and found last week that schools without mask mandates are seeing two times the number of cases as districts with mask mandates.
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The data comes from COVID dashboards from 33 Houston-area school districts.
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