Actually, it’s a bit long and involved and probably would work much better if broken into two or even three sentences.

Something about your second sentence bothers me. Yes, I understand what you’re trying to say – could it be you should continue on with Elaine’s problem being ignored/getting noticed instead of other people’s standing out? Give a concrete example of how she isn't getting noticed rather than a vague generalization of how other people are standing out? And it would be nice if that concrete example segued into her old friends somehow.

Then start a new topic in a new second paragraph - her mom dropping her off here. I’d skip the letters from the friends. That’s too upbeat when she’s on a good depressing funk here. Go on with a bit more about how miserable this is, abandoned by mom. Then a sort of beat as she slouches. Another bit that is a concrete not a vague generalization…maybe just use that to bring out the key.

By the way – it had been laying WHAT in the dirt? Eggs? Lay, laying REQUIRES AN OBJECT!!!!

Oh, you must have meant it was LYING in the dirt. Didn’t you?

Fiddling with the key in the middle of a geometry lesson or a poetry reading and nobody notices might be a lot more visual and interesting.

...it wasn't the typical found in the dirt type of --- huh? Typical what found in the dirt type...you need to fix that. I assume you do not mean typical key found in this type of dirt -- do you? The typical what -- you really do need to say what.

My initial reaction is that it reminds me of so many intros to stories I've seen in literature textbooks. And those stories are chosen for those textbooks for good reasons. Among other reasons, they have great intros.

Elaine sat in her stiff school uniform and felt invisible. But then, wasn’t that the point of the uniform in the first place, to make sure no one stood out. Except it didn’t work. People still stood out, just not her.

Send it my way, please.