Not only Volunteers played Kampfspiele or other games to increase the military capabilities. All Hitlerjungen had to do.
Among the many games Hitlerjugend played there are some that had been very usefull for Flakhelfer. Wiking (famous for the 1/1250 ship models) produced a big range of 1/200 plane models. Flakhelfer played recognition games with them. There are booklets for that. Hallen Kampfspiele by Willi Hennig was a rule book for indoor fighting games used by HJ. The monthly HJ magazine included many rule sets for outdoor training games.
Handgranaten Weitwurf (Hand greande throwing) was still teached at schools in the former DDR, together with other Vormilitärische Ausbildung (military training) things.