Question: I had a HUGE drop in GPA in the second semester of my sophomore year and first quarter of my junior year. The rest of my junior year was very good, and I expect my senior year (about to start) will be, too.
I have had no loss of life in my family or divorce of my parents, I simply didn't concentrate in school. The reason I didn't concentrate was because I was too busy trying to "strike it rich." I spent my time investing what little I had in stocks and internet marketing plans.
I'm going to write my college essay about how this mistake cost me my GPA, how I learned from it and bettered myself. Is this a good plan or is it a bad idea to use my essay to highlight a mistake I made rather than one of my achievements?
A college essay--whether it's an official, required one or an unsolicited, supplementary one--can be a good way to explain irregularities in your personal life, education, or transcript. So, yes, do take advantage of the chance to tell your target colleges about your drop in grades.
You explained it nicely to us ("I was too busy trying to 'strike it rich'") and you should certainly convey that information to colleges as well. The topic could even lend itself to some humor, which is usually much welcomed in admission offices, as long as you also show admission officials that you're serious about the lesson you learned from your mistakes. And this message should be credible because your GPA bounced back to what it was before you were off on your gold rush. Also make sure that your senior year gets off to a strong start as well. It's a prevalent myth that 11th grade is the one that "counts" with colleges and that 12th grade is almost irrelevant That's actually not true at all. Colleges will pay close attention to your first senior semester so do make sure it's a good one.
Meanwhile, save those get-rich-quick schemes for when you're out of school and have a steady paycheck coming in. :-)