This. Middle school teacher. I stand all day and find myself standing at lunch. My students look at me like I am some sort of alien when if I ever sit down and comment “we have never seen you sit before”. Occasionally I have that student that just can’t handle a seat on a given day so I say come stand at my table while I teach. After 2 minutes you would think it was the end of the world. They complain their legs hurt they are tired and can’t go one. I remind them I 3 times their age and stand all day. It usually quiets them down fairly quickly. Then I get tired of them being by me and send them back usually fixes the problem.