Skip these periods of online learning altogether (they last no more than a week or two to six, I guess), and let them play and learn on their own (with guidance and support, if needed). I feel their brains are still so absorbant that they’ll pick it up once the offline schools are back at it again. Plus, (outside) playing, at least where I live/what I (don’t) witness, wouldn’t hurt anyway. Children can use some extra play time, is my opinion. Not to mention (team-) sports/fitness/gymnastics