Well, she did say that at the beginning, but it seems to have been a gaffe, because later she was claiming the science does support opening schools.
In any case, equally disturbing is the apparent open strategy that, yes, all schoolchildren will get infected. But that’s “OK” because the young don’t get hurt too bad. And “the science” does seem to support this. It’s just that, obviously, all these contagious schoolchildren will come in contact with adults, killing some of them.