Several teachers were also affected by the incident just before spring break in March.
Students in the Swiss city of Basel falsified positive COVID-19 results in a bid to skip school, resulting in the entire class being put in quarantine, and now disciplinary measures against the perpetrators after the hoax was discovered.
Three students in Basel's Kirschgarten High School falsified SMS messages from Switzerland's COVID-19 contact tracing app, the Swiss newspaper Blick reported.
That forced about 25 classmates to be confined to their homes for some 10 days. Several teachers were also affected by the incident just before spring break in March.
"This is not just a childish prank, this is a serious incident," Simon Thiriet, a spokesman for Basel's education department, told Blick.
The school plans to pursue criminal charges for falsifying "health-relevant documents" though it does not plan to expel them. Thiriet said that students are in a "difficult situation" due to the pandemic, but that doesn't excuse the threesome's stunt.