I’m going to be a senior next year and I’ve been on the volleyball team since freshman year. If I continue onto senior year, I would be a part of the varsity team (I’m on JV now). However, I’m geniunely getting tired of the sport; my enjoyment for it has faded and it takes up a huge chunk of my time in the fall. I take all APs and I will continue that rigorous schedule my senior year. The only thing that is making me question my desire to quit is my worry of not having the “commitment” and continuity that is so coveted in college apps. I’m not a volleyball recruit or anything, so will quitting even have an effect on my college app? My dream school is John Hopkins, and so I’m worried that this will give off a slightly negative impression, as a lot of my extracurriculars already seem like “padding” activities.
I did track 9th-11th grade, and am quitting this year (my senior year). I’m also applying to Yale, Brown, Pomona, and other highly regarded institutions. I wouldn’t worry about it. 3 years is still a lot of effort and you definitely shouldn’t continue if you’re feeling burnt out. In 11th grade I tried managing work, 5 APs, and track and it took a major toll on my mental health so don’t make the same mistake!!! Best of luck in whatever your decision ends up being 
i’m a senior now and I played for 3 years and quit this year. i don’t think it matters too much tho, however I was a captain for the team sophomore and junior year for JV. though, i also have another varsity sport i’m playing for 4 years that i’m a captain of. however, i think your fine, especially with such a rigorous course load and if you have other important ECs.
Colleges will look at it and your courseload and probably question your classes. My advice is don’t quit. Colleges don’t want to see you stop extracurriculars because your classes were too hard. If they strongly impact your grades, then you should quit but if they make a minimal impact, then continue.
I assume that you are applying to JHU ED because that probably has a more positive effect on your admission than whether you play volleyball.
Nobody knows if it matters. You have a binary decision to make and there are 4 possible outcomes.
I made a happiness table to value your outcome. You can make your own.
You continue with volleyball - are unhappy, don’t get into JHU anyway - most unhappy - 0
You continue with volleyball - are unhappy, get into JHU - happy, but exhausted - 2
You quit volleyball - don’t get into JHU - unhappy and possibly regretful, but you’ll probably do better on your APs - 1
You quit volleyball - get into JHU - double win - really happy - 4
If your probability of getting into JHU is 0.4 with volleyball, and 0.2 without, you are still happier quitting volleyball.
If your probability of getting into JHU is 0.2 with volleyball, and 0.1 without, you are still happier quitting volleyball
If your probability of getting into JHU is 0.5 with volleyball and 0.1 without, you are happier playing volleyball.
In other words, it has to matter a lot for your admissions. I would guess it is not worth more than half of your probability of admissions and that you would be happier quitting volleyball.
You could play with the numbers on a spreadsheet and see if it helps you decide.
It’s an oft-asked question. Since you’re not going to be recruited, I think it’s perfectly fine to drop the sport. Your interests change and colleges want you to make wise decisions – (not based upon some CC myth about “what looks good to colleges”).
To bear down on harder classes, college apps, whatever – is fine IMHO.