Sorry for the late reply. You raise an excellent question. You can leave the 3-month job off the resume, and if you use years only in your resume (as opposed to months + years) you can also leave the gap off the resume. However, you must account for the 3-month employment in the data section of your application (unless the school's instructions say they only want you to list jobs at which you worked over X months or similarly). The difference is that a resume is a marketing document that, while it cannot contain falsehoods (and should not exaggerate), need not include everything since it's focus should be on *relevant* experience for the position you're targeting. The data section on an app is a different animal altogether, where you have to account for gaps. So, yes, assuming that the 3-month gig will be mentioned somewhere in your app, you should *briefly* address it in an optional essay. It's hardly a mark of shame, and in fact you are to be congratulated for having returned to the better gig. Explain to the schools what you explained to me (with a little more detail), but keep it short and sweet.
Hope this helps,
Co-Author of: MBA Admission for Smarties: The No-Nonsense Guide to Acceptance at Top Business Schools
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