LAF, each of my kids first practiced keyboarding with BBC-Mat, which is online and user-friendly for little folks
We also had a typing software package that we tried to move our oldest into after he'd completed the BBC-Mat program, but he wasn't interested in it. Ultimately what worked the best for my kiddos to learn typing was to let them practice it without typing software - practice by writing stories on the computer, sending emails, playing games that required text entry.
A big piece of advice we were given early on (by professionals) was to not force our kids to use conventional touch-typing, but to let them come up with their own form of adaptive typing. Don't worry if they only use thumb and first fingers or if they have their own set of finger-key preferences. Ts worked really well for our kids, and they haven't had any issues to date typing fast enough to keep up (they are in middle/high school now).
I also wouldn't over-focus on teaching keyboarding just because of the testing on computer at school. I'm guessing that your school will also be teaching skills to help kids do their best on the cc tests, so they will most likely teach whatever test taking skills they feel the kids need. At least that's what happens in our district! learning to keyboard is a worthwhile skill for lots of other seasons outside of the cc tests though, and it can be fun!
Best wishes,
polarbear
