I am interested in medicine because I love science, but I only have four science-oriented extracurriculars and I am not sure how many I would need for a spike.
This is an excellent article written by CollegeVine on the subject of the applications spike.
I highly recommend you read it.
https://blog.collegevine.com/how-to-find-your-college-application-spike/
Everyone has a different opinion on what a spike is. I tend to think of it as reading someone's EKG or the output on a lie detector test.
You see different reverberations and a blip or spike which is the heartbeat of the person. Sometimes the blip has a lot of amplitude like a bolt of lightning, and other times not so much. It's rare that someone has a double or a triple heartbeat.
Similarly, I think most college applicants can narrow down a spike to what they are most passionate about, that could be being a "math geek", "a ballerina", a world-class "rock climber", "a painter", an "opera singer" or simply a compassionate "activist" that uses their platform and voice to serve those that can't serve themselves.
When you fill out the Common App, or the Coalition App, or a Merit Scholarship opportunity, there are always 6 to 10 slots to put your extracurriculars in and explain them. This for the application reader to get an understanding of what your playing field looks like. But they can't or not supposed to be all "spikes". The spike or spikes on your ECs are primarily the singular or in some cases the two activities that you are exceptional at as evidenced by your track record, honors, awards, or some metric that separates you from the fold.
So for example, you might love STEM, be good at programming, math, statistics, biology, chemistry equally but that's not necessarily a spike. But if you apply these and create say a "contract tracing" app that 10,000 high school kids used in 5 neighboring school districts and alpha and beta tested the whole process, and are now planning to roll it out to other schools, etc., well that's a spike for applying technology to help society. And that's what you would write about on your application. Often unless one can run 1500M under 4 minutes, a spike is multidisciplinary or multidimensional.
Why elite colleges seek out applicants with unique spikes is because a.) they are curating a freshman class of academic, athletic, artistic curiosities that makes for an interesting presentation on their campus. b.) students with amazing spikes usually are those who also can "connect the dots", those that can "zoom in and zoom out" of intellectual pursuits and share their experiences in thoughtful ways and leave their ego at the door.
The last thing I would say is that a spike doesn't have to be related to your major or the profession you want to be. I have a friend who just graduated from Columbia U. who is the worst demographic, sis STEM-oriented Chinese American. When she applied her spike was being a national level rock climber/boulderer. She had minor smaller talents in music and painting as well.
Hope that helps and good luck with developing your spike activity.
So generally a spike is the core component of your application he thing is without surrounding items you don't have a core. So only 4 spike activities is absolutely fine. Depending on the application you'd have 8-10 EC spots and 4 of them being science related is really good.
Hope this helps and feel free to comment for clarification as Id be happy to help.
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