Good afternoon.

I have a builder grade Moen knob bathtub handle in my guest bath. The off position, rather than being at "12 o'clock" is at "3 o'clock." I can turn the handle counter-clockwise to "9 o'clock" for ice cold water. I can also turn the handle clockwise to "7 o'clock" for nothing but extremely hot water. Give this my kids bathroom, it's not ideal.

Is this something that I, knowing nothing of plumbing basics, can remedy, or is this more in line for a professional?

Many thanks.

How do you turn the water on and off? Do you pull the handle out to turn the water on and push it in to turn the water off?

No, sir. Just turn.

I have the same setup on my Delta single handle. Hot full right, cold full left, mixes in the middle. My question is "what is your concern "?

My concern is there's no control over the temperature and this tub is for my kids. It's either ice cold one way, or scalding hot the other. We annoy control the temp.

No, sir, OFF is at 3 o'clock

Try this.
Remove handle, turn cartridge 180 degrees and reinstall handle.

That seems easy enough, is the cartridge easily identifiable?

Remove handle then turn the stem to which it was attached half a turn with a pair of pliers, reinstall handle.

I am in agreement with Harold but he forgot to mention that you must pull a brass clip out before you can pull and rotate the cartridge. I think you are still going to have a proble, a rotated cartrdige just reverses hot and cold. I think you have debris in the cartridge. You can clean it or get a free replacement from Moen Strange booster pump - Ask Me Help Desk (https://www.askmehelpdesk.com/plumbing/strange-booster-pump-775974-new.html)

Well, I am easily able to remove the cartridge? But after that I stall. I cannot seem to adjust the shut off position from 3 to 12 and am not able to control the temp.

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