Is it advisable to fill out all 10 of the ECs on the Common App? If I don't have 10 ECs do I need to worry about finding more last minute, or will 5-7 ECs be enough? I didn't hold school-level leadership in any of my clubs and seniors cannot apply for leadership so should I be worried?
The number of extracurriculars you participated in doesn't speak as much if you didn't have a passion or role in them. I would suggest including the clubs/activities you participated in that showcase your personality and interests in the way you'd like the college to perceive you. So no need to worry, as long as you were active in the ECs, that's what matters most.
ie: Rather than listing off tens of honor societies include interest clubs like gaming, anime, or even knitting.
I think it is ok if you only have 5-7 as long as those EC's are high commitment and meaningful and reflect your passions.
Whether you have 5 or 10 ECs doesn't matter. What colleges really want to see is that you're utilizing spare time productively in activities that are meaningful to you and contribute to your personality. They want to see your dedication and passion for non-academic activities. Leadership opportunities are limited, so it's obvious that not everyone gets a chance. Don't worry about that.
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