Since they don’t really care how many are infected; the truth is that they really only care to ensure that the maximum number of parents are scared into gettng their kids vaccinated. Then, when the vaccine doesn’t work and the kids are infected because the schools won’t take the proper precautions, the maximum number of child bearing age adults will be sickened and die. And that’s precisely what they want to happen.
Since idiot parents bring their bored kids to the mall, movie theater, etc., where said kids interact with their peers and defeat the purpose of the school closures.