N=1, but childcare has been the biggest avenue of infections I've seen here in Germany. Basically every childcare of colleagues with children has been shut down at one point in October/November (when the numbers started rising here) due to infections among the children. In most cases one or multiple of the families have been completely infected as a result of that, and I guess the only reason it hasn't spread around the workplace is due to good precautions.
I have exacty the same suspicion. Cases started spiking exactly 3 weeks after we opened schools after summer break in Poland, and did not start falling down until we closed down schools again.
N=1 as well, but we haven't seen a single case of it. In the area, I'm aware of one school that had a case of COVID a few months ago, and our local one - in which our child is nominally enrolled, but isn't attending physically - lasted with zero cases until two weeks ago.
Same in my family. Kid was fine, grandparents just couldnt live without seeing her weekly (slaps forehead :/) so got infected (one critical condition at one point), so did the parents.