Parents worried about how much time students spend on iPads and laptops during school are trying to opt their kids out of classroom tech. They’re finding it isn’t easy. Cellphone bans are taking effect in big districts across the country, including Los Angeles and Las Vegas. The next logical question, at least for some, is: What about the other screens? These concerned parents argue that the Covid-era shift that put Chromebooks and tablets in more students’ hands is fueling distraction more than learning.