pattern the gun with shells and chokes you can find and see what the gun shoots the best. get it shooting dead center and pass the test yourself...then let her shoot and get used to it so she can do it.

not sure of your daughters age...but a magnum load through a 20ga is going to give a good thumpin...so thats why i say you do the shootin till you find the load and choke combo the gun likes...can get kinda expensive..but buckshot can be had in 5rd boxes so it shouldnt be bad...and finding a killing load should be #1 on the list of things to do....even more so being she has to qualify...

good luck