Do colleges find out when you join a club?

I'm thinking about joining a new club in my junior year. How would colleges know I'm part of it and does it look strange to join so late in high school?

Colleges will not automatically know if you join a new club. It's your role to inform them during your application process by providing thorough and accurate information about your extracurricular activities. When filling out your applications, there's typically a section where you can list your involvement in clubs, leadership roles, and how long you've been a part of them.

Regarding joining a club in your junior year, that's not unusual or detrimental, so long as you are genuinely interested in the club and active in your participation. It's more about the quality of your contribution than the quantity of your involvement; demonstrating genuine passion, drive, or changes and impacts you've made to the club can leave a good impression.

For example, if you join a debate club in your junior year and become an active participant, develop new debate strategies, or even help the club win competitions, it’ll potentially be more meaningful than mildly participating in ten other clubs since your freshman year.

Finally, you have the option to explain your late involvement in your application. If it coincides with a newfound interest, for example, you could use your essays or additional information section to detail why you joined the club and what you gained from it. This could potentially add depth to your application.