I've avoided playing chess most of my adult life. so I never learned about famous endgame positions and puzzles.
I've learned a few recently through Schultz's work. He has several chess-based puzzle games that teach principles of few-piece chess positions, including a few mini-puzzles that teach a single position.
This one involves a setup where each side has the king and 1 pawn each.
I found it enjoyable, and liked the backstory. But I spent a long time on it due to encountering a bug in scenario 2, which I forwarded to the author; essentially there is an unintended solution to that scenario, so I couldn't figure out if my unintended solution was blocking the 'real' one of if I could still solve it. I looked at the walkthrough and found one line that more or less gave away the second solution, to both puzzles in fact (the line was that (Spoiler - click to show)the king can only focus on one pawn at a time). If that bug were patched, I would definitely put 4 stars for the rating.
As a side note, I think this game struck a good balance between 'let the player keep playing in a losing position to see why it's losing' and 'cut them off right after the first mistake'. One quality of life change I would like to see is a more dramatic heralding of completing one of the scenarios. Right now, it is very similar in appearance to losing, so if one is repeatedly replaying quickly to try different strategies (especially since there's no undo), the text can blur together, so some kind of major break (like bold, or a line of asterisks, or some other signifier) can be nice. The counter in the corner does go up, and that's the main way I noticed the scenario number increase.
Overall, it's been fun to learn more about chess through these puzzles.