Nice to see the "maker" in here. While the fretted may be a good idea for some adults, I would be concerned about a child getting used to using them, thus NOT training their ear.

My early violin teachers would have been appalled at the thought of frets, no offence, Peter. They might be useful for a very young child, such as my almost 4yr old grandson who wants to hear a tune as soon as he picks up his fiddle but doesn't quite have the patience for how to do that, yet. He does have a good ear, though, so I think we'll stick with the tried and true learn by ear.

McGrath, I look forward to your posting after you've had a chance to try it out.