Testing kids for COVID-19 is the kind of hygiene theater that has the FAA telling air travelers to take their masks up and down each time they take a sip of coffee. There is evidence testing for COVID-19 in schools is minimizing the impact on education while not much it is minimizing the spread of the virus. Nearly everyone over the age of 50 who intends to get a vaccine has gotten one and most kids are at low risk of having COVID-19 be anything more than a cold.
Teens may be providing another reason it's unnecessary;
they are using Coca-Cola and lemon juice to fake positive tests to get out of attending school, a Ferris Buehler's 10 Days Off strategy.