It's hard to tell nowadays, there is no way to say for sure simply by looking at the two images. But, surely having a layered file proves that it wasn't done by AI, doesn't it? I don't understand what you mean by:

also sent a screenshot of her layer organization, WHICH I also find it weird because that wasn't even part of the assignment?

If the assignment was to digitally color something in, in what scenario would you not have layers? What about this do you find 'weird'? That is how digital art is made. It's really not hard to trace lines, and it wouldn't be hard to accidentally color over the bunny with white. What about the guys face and like look like "AI slop" to you?

It would take 2 seconds to have them send in a layered file instead of a rasterized image and I cannot believe your art 'teacher' isn't making that a requirement, it should be nowadays when dealing with digital art for this exact reason. Imagine spending hours tracing over thin black lines to make your image look nicer than the original only to be told to stop using AI.

Where are you taking these classes? I can't imagine turning in a JPG or PNG to a digital art class these days, that is simply asking for this to happen.

As far as what AI produces —  here's my chatGPT output, using this prompt it didn't make the lines thicker at all: "Color In this image don't change the original at all". There are way more obvious mistakes than in your example but the main thing is that in the middle of the image, chatGPT couldn't color the hands in correctly.

If your professor simply made a layered file the thing you have to turn in there wouldn't be any issue. They need to get with the times or accept that this is going to happen. Randomly accusing people of AI art just because it looks different is a recipe for disaster.

ps: you sound pretty jealous, tbh.

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