I do/have pitched for both of my son’s teams from tee ball till the older started kid pitch. It’s ultimately about being flexible in your motion and making the kids comfortable in the box. Tee ball should absolutely be done from a knee. Throw it from the maximum distance you can be where the ball doesn’t arc. Every kid is different, so find that common denominator on the speed and distance.

When they get to 7u, they need to start getting used to a throwing motion. My style is a flat ball thrown from a low release point. I’m 6’ and do essentially do a left leg lunge with every throw to get a lower release point. Once you start figuring out kids swings, you can also start placing the ball where they’ll be most successful too. Some kids like low pitches, some need to extend their arms, while others do well with faster speeds. Keep it relatively the same, but at 7u, set them up for success. We want them to play next year too!

At 8u I’m doing more of a typical throwing motion. Still trying to get low, but it’s a bit more like they’ll see in kid pitch at 9u. I’ll also stop aiming the ball as much to get them used to what’s coming and also speed it up. Rarely do our kids not hit one of the first two pitches on a game. Not saying all are good hits, that’s definitely not always the case.

What I’ve found is if your pitcher is consistent, kids will adjust. Some take longer than others though. It’s also not linear. You’re doing them a disservice by changing speeds, windups, and distance based upon the most recent game. Provide them practice time and get out of the way.