Stacey Ebert, Educator, Writer, Event Planner, Traveler
Extracurriculars are extremely important to your high school development, college career and building blocks of life. As others mentioned, it's more important when applying to schools what you've done in those organizations rather than being in a greater number. Yes, if you were to match two exact GPAs and student applications and one stood out more in their extracurricular pursuits, it's more likely that person would have a greater chance of getting into the school.
Find some groups at your school that might interest you. (If there's nothing at school, look elsewhere in your community to get involved) Perhaps it's community service, an honor society, a theater group or a full class organization. Show up, voice your opinions, volunteer, help out, get involved in any way you can. If it's something you enjoy you might be able to find a leadership position or role in the organization and those are the things that stand out on an application. As an advisor and someone who interviewed many students for university, admissions know it's not the amount, but the time. Being a member of five organizations is different than holding a position in one. Showing up to various meetings or walks is different than planning Homecoming or the Junior Prom. Being a member of the honor society is different than holding an officer position for more than one year of any club or organization. The time spent on each project makes a huge different and yields a different result according to those reading thousands of similar applications. Perhaps there's one that you can devote a lot of time to and it might even completely change your high school experience for all four years.
Also, students who are involved in organizational leadership work with a variety of staff, faculty and peers throughout their high school career. You might get to know more people and develop significant relationships that help your development. As an advisor, I worked with many incredible student leaders. Watching them develop, learn, share and involved themselves in so much was wonderful to watch and made it exceptionally easy to write a glowing recommendation for them when the time came. There's a lot of informal education and learning that goes on in extracurricular clubs and it's not to be missed. Your involvement will not only make an impact on your application and resume at a later date, it will supply you with skills, bring out talents and enrich your high school career more than you could ever imagine. Get involved and enjoy your after school activities - those are many of the memories you'll have when your high school career is over.