Being impressive is a good thing. But trying too hard to be impressive usually isn't.
Imagine you were on a first date with someone and he blurted out, "I've done over 200 hours of community service at the hospital. In fact, I won an award for my hard work and dedication." Sure, that's impressive. But you'd also probably feel like he's trying too hard.
Confident, self-assured people don't try to wedge their accomplishments into casual conversation. Nobody likes someone who can't wait to tell you how great he is.
But if your date had just said, "I volunteer at the hospital and get to work with some pretty great kids," you'd want to know more. You'd ask him to tell you more about the kids, what kind of work he does with them, and even how many hours a week he volunteers. Then he wouldn't seem too full of himself when he revealed how many hours he's spent there–after all, you asked. You'd probably be even more impressed because you'd have a better a sense of how much this work really means to him, more so than you would have if he had just shared the impressive statistics.
Filling out your college applications (and writing the essays) works the same way.
When a college asks you to list your awards or to tally up how many hours you spent doing an activity, that's the equivalent of a date asking you, "Have you ever won any awards?" Don't be bashful. Answer the question, and be proud–you deserve it.
But when you wedge hours and awards and accomplishments into the other parts of the application, it sounds like you're trying too hard.
When a college asks which of your activities has had the most meaning for you and you list all your awards, you're trying too hard.
When you write an essay that's all about how your time in the Model United Nations taught you many important life lessons about hard work and commitment, you're trying too hard.
And if you complete community service hours, secure leadership positions, and live your high school life based on what you think will look good on your resume, you're trying too hard.
The most impressive students are the quietly confident ones. These are the students who want to learn, who commit themselves to activities they really care about, and who know that their hard work will pay off no matter where they go to college.