The following are videos that demonstrate some of the techniques needed for youth testing:

in the  Kyu test for 10A  you will need to do a Jo Suburi for Shomenuchi

in the  Kyu test for 9A  you will need to do a Jo Suburi for Tsuki

In the  Kyu test for 8B  you will need to do the 13 count Jo Kata (Waite style)
13 Count Jo Kata solo and paired practice 1:57 (Robert G and Katherine R) done using the Donovan Waite form (affects the solo practice with a turn in the middle). You will only have to do the individual, not the paired practice.