"Get up, go run to that tree, and come back" was sometimes at least somewhat effective, particularly with younger children. Also, getting up and moving for a minute helps with learning anyway.
Yeah there's fidgety and then there's leg jiggling so aggressively that the entire row of desks is moving and I'm not even noticing because I am so focused on what I am writing down.
Also in adulthood I was finally properly diagnosed with "moderate to severe ADHD". Probably should have done that in highschool when I told my parents but what are you gonna do. Can't change the past.