I considered Bikeabikity as a trainer, but im not sure I could be sufficiently de-programmed from my professional cycle teaining to make it work. Teaching kids to use a bike as a weapon might not go down well.
Very well done to your granddaughter Tenkers. Its good to see the young uns still wanting to ride. Sadly Mini D #4 is autistic and freaks when sat astride a bike so I've never pressed the point with her. Oddly, when I used to meet her from school, she was fascinated with my folder and always insisted on pushing it home. Kids, eh?
Mini D's #1 and #3 still have bikes and still ride for pleasure, and I gifted Mini D #3's fiancee an MTB so they could go on rides together.