How to send extra information

All of my schools had app deadlines by at least January 15th.
My dilemma is that I created and organized a tampon/pad drive at my school about mid February and I have no idea how to let my colleges know about this. It’s taken up a lot of my time but I’m very happy/proud with the outcome- it’s also the first major project the club I started has done and I mentioned the club in some of my essays. I’m hoping this information may be a nice follow up.
Should I email my schools with this information? If so, what would the subject line be? “Additional Application Material” ?
Thanks!

Yes you can but you can also be pretty much assured that it won’t make a lick of difference. The colleges are DEEP into their lists. You can bet your file has already been read and acted upon. But your email and email title is fine.