One of the real issues for children is we didn't have a supply of masks designed for them. We only had access to cheap cloth and paper masks designed to fit adults.
Another is the cheap cloth and paper masks that were available the 1st year were not designed to prevent covid infections, they were only for reducing the distance covid would spread in the air when breathing and coughing.
Where I live, most of the very conservative folks who live here (78% of the population) flat out refused to wear a mask and made a point to boldly walk into stores cocked and primed to take anyone on who told them they must. I wore them and was snarled at everywhere I went. Fair to say their children were taught to refuse to wear them too, and that while required to wear them in school, almost none of the schools staff enforced that here.
So, yeah, if you analyze the effectiveness of masks reducing covid infections in children here you'd conclude they did not work, but you had to be here to know why.