OK, first of all, your game is fantastic! Pretty, simple, and challenging. As a full-fledged adult, even I have to scratch my head at some of these. That said, the challenge isn't arbitrary, but down to being smart enough. The hints are good at letting the player piece together the puzzle themselves while giving them enough to work on when they are really stumped. Well done! I especially like the photographic memory mechanic. I wish more puzzle games employed this approach.
SPOILERS AHEAD (for bug report)
That said, I encountered a bug. All I did was keep pressing the item while the cutscene was processing to extend the telescope. Now I can't choose anything from my inventory. I cannot give her the telescope. I had to refresh the browser but THANKFULLY we can retain our progress. Another amazing feature.