The Moore method is indeed designed for undergrads. That is how I learned point-set topology, a marvellous experience for a small class consisting of 3 senior honours mathematics students at UBC. I have sought to incorporate elements of the Moore Method when I have students, and classes, with appropriate characteristics.
It is good to be open to new and different ideas. Moore merely formalized a method that has been used by academics with ambitious students since the time of Socrates.
But you must realise that there is a fundamental difference between how a novice and an expert learn best in a discipline. It is a bad idea to generalize from the experience of a young adult student with advanced background in a subject to that of small children with no background in it. That is why I advised you to read about the expertise reversal effect.
This is a well-established principle in cognitive science saying that understanding and mastery are improved when experts are led beyond their current level by challenging them with individual inquiry or exercises in extension of that expertise base, following the excellent models laid down in their earlier learning to explore new parts of that realm … and at the same time, novices learn more slowly and more poorly under the same kind of tutelage. The principle applies to all forms of discovery, inquiry and the Moore Method (which is neither of the above, at least not in any sense that pertains to what public school teachers are encouraged to use under those rubrics). More generally, cognitive scientssts speak of “Minimal Guidance Instruction”, and they have well-established experimental results which show when, and in what circumstances it is effective. The general gist: not a great idea for primary grade novices.
To help you get started, here is a helpful summary of what’s known andhow cognitive scientists interpret the meaning of the data, by three world-renowned cognitive scientists: