What they did is part of history, but that's not quite the same thing as "history-making". Again, they've broken no new ground whatsoever, nor have they done anything particularly unique and unusual. I recognize your desire to idealize and idolize these kids - perhaps to compensate for regrets about your own unrealized adolescent dreams, who knows? - but it doesn't change the fact that they haven't done anything really meaningful and substantial. This is actually par for the course for the vast majority of such upheavals, and ultimately probably a good thing, since all too many of the ones that HAVE produced something substantial have done so in ghastly ways (again, I direct your attention to the French Revolution).
Furthermore, on the subject of "adults were not able to do anything" and "I didn't see", you should really investigate the difference between "What I heard about from the media" and "what has actually happened". The fact is that numerous changes have happened, back and forth, on the subject of gun ownership and gun violence over all the years since the US Constitution was ratified, and every single one of those changes, good and bad, was implemented by adults, not children. The statement "nothing has been done about guns" is either a misstatement based on ignorance of history and the laws, or an outright lie based on a REAL meaning of "my personal preferences have not been implemented".
If what you want is a fairytale land where guns were never invented and don't exist, or the next best thing (in your eyes) of a complete ban on any projectile tool which scares you, then you're correct that that hasn't happened, nor is it ever going to, nor do you have a right to expect and demand it. It may surprise you to realize that YOU are not the only person who lives in this nation, or who has a right to have their wishes and goals considered in public policy. It is also entirely possible that other views besides yours may have valid points to make (I know, what a shock). And amazingly enough, it is not only possible, but likely, that other people can care just as much about loss of life as you do and still disagree with you on how to prevent it.
Finally, on your remark about "These kids will do it for you whether you like it or not." Will they, now? How are they going to manage that, precisely, given that none of them can even legally vote at the moment, much less run for public office? You WERE aware that that is how public policy is changed in this country, by votes at the ballot box and in legislatures?
I would also like to point out, in conclusion, that your implied threat of "whether you like it or not" sounds remarkably like fascism and the complete antithesis of America, where the whims of a few are imposed on the majority without their consent and by force. Is that REALLY what you want to advocate and express enthusiastic admiration for?