Thank you so much for playing, as well as for taking the time to comment ^^
I thought of the same exact thing while reading Metamorphosis. That ended up being my entire motivation to make this game ahahah ^^
[SPOILERS BELOW]
Other than that, you're basically right about everything you mentioned! Regarding the homework specifically, it is mentioned that Maisie is a straight-A kid, and some parts of the game implies that the main character might not be that close to her and doesn't know her all that well. She was indeed testing him, you are correct about that ^^
The second ending is the one you get if the MC completes pupation, but still wishes to return to his old self (the pupa) but of course, a change like that is impossible to undo, so the cycle simply starts all over again.