Do you now want to believe research coming out of China? Because that's the originally referenced material.
Also, this was accepted back on March 18th. You don't think anything has developed since then?
The Swiss studies references happened when schools were closed. They found a child was the index case not quite 10% of the time in that circumstance (plus, implications for the US, that's a pretty big number when you consider all the students around the nation flooding classrooms during the worst flareup).
I'd love to be able to accept that outright--but as always, we have conflicting information:
Coronavirus: Can kids spread COVID-19? Your COVID questions, answered
Lots of kids asymptomatic or mildly symptomatic. That's great for general health, but terrible for possible community spread. And that's without schools open--notoriously bad vectors for disease spread and general health. Knowing what we know, it's a bomb just waiting to go off and an unacceptable risk given there IS an alternative to jamming kids and teachers back into their classrooms to spread back to their homes and communities. Schools are basically the center of just about every community. I'm not down to use my kids to test hypotheses.
We need to err on the side of caution and the unknown, not on the side of possibility and convenience.
Edit: Also
https://www.nap.edu/read/25858/chapter/1
“There is insufficient evidence with which to determine how easily children and youth contract the virus and how contagious they are once they do,” the report says. This knowledge gap “makes it extremely difficult for decision-makers to gauge the health risks of physically opening schools and to create plans for operating them in ways that reduce transmission of the virus.”
The LA times writeup seems to argue it's progressively safer for younger and younger kids to go back, but that quote from The National Academies of Sciences, Engineering, and Medicine sums up my thoughts. Not enough info.