I wasn't sure whether 8 was really the right age to start facilitating programming, or whether I really should steer clear of screen time as much as possible, but it appears that DS8 really benefits from the mental exercise. (Will still try to get him out and about and moving as much as possible this summer!)
DS has been taking mind storms and scratch classes at an enrichment academy for gifted kids offered for third and fourth graders (open for all kids with teachers recommendations, and as it's in a fairly rural area, it does appear to reach the kids who are really interested, no tiger kids around) and loves it. Yesterday, after his third scratch session, the instructor took me aside and asked whether DS was enrolled in the scratch workshop scheduled to start in a month when the introductory classes were over. "Because he should be moving ahead at about twice the pace I am going, and I can't go any faster because I'd lose the other kids, but in the workshop, everyone can move at the pace they need." Considering they other kids are mostly fourth graders, presumably gifted ones, I was really proud, and yes, he will be enrolled in the workshop and hopefully busy and happy!