You are grossly over generalizing. Unless you have been privy to everyone’s college applications, you will never know why John got into Harvard but Jimmy didn’t. You have no idea what their teacher recs said. You don’t know what their grades and test scores are. You don’t know their personal circumstances. You don’t know what all their essays and supplements say. You don’t what attributes John’s application displayed, and what Jimmy’s did not.
Writing about your income level and life challenges could be a good essay, but it is all about how you convey your personality. I’ll blunt: they don’t admit people because they feel badly for them. You want them to want you.
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