She is shooting a single shot 22 in the NRA right now. She enjoys it very much. That will be what we get her...and she will help her little brother learn before he starts the NRA.
I applaud you. They are learning good skills and how to handle and respect a firearm.
I started with a .177 air rifle at about 9 years of age and then graduated to a .22 Marlin bolt-action rifle when I was 12 or 13. I still have the Daisy air rifle and the Marlin as well as a Lee-Enfield No.4 Mk.1 and a Gew.98 8mm Mauser. I am looking into buying an SKS, a Ruger mini-14, or a Schmidt-Rubin M1931.