Should you do it for the Extra Curricular credit? Probably not. But if learning about how different kinds of emergencies are handled and getting a pretty good overview of what it's like out there in the field, you should totally go for it.
Ditto what was said above, with one amendment. Only take it if you plan on using the certification for work as an ER tech/paid ambulance company or a volunteer EMS position. I took an EMT-B course freshman year of college and I'm so glad I did. The class did cover a lot of basic first aid and CPR stuff, as was mentioned above, and it can all be learned on your own. That I won't argue with. But we learned how to do histories and physicals, take vitals, and make minor medical decisions, all in emergency settings, and those experiences were unique to the course (although, I'm sure you can do that on your own, too, if you're dedicated enough and have very understanding friends).
It was nice to be able to do some sort of medicine so early in the process of applying to med school, and it is much more than any of my other pre-med friends ever got to do, especially if you go on to use your certification for some sort of job for an ambulance company/ER or even to volunteer and use your skills.
I worked for a 911 only ambulance service for three years after getting certified and those were my favorite parts of college. Although I technically was only allowed to do basic stuff per my certification, I often worked with a paramedic, or would get a call that necessitated a medic, and thus was exposed to many real, emergent situations. I learned a lot from working ALS calls with these medics and it was a very worthwhile, educational, and super fun experience. I got really lucky because we had a very high call volume and all calls were 911 so we had no transfers and technically were only called to emergency situations. Unfortunately, "emergency" means different things to different people and so we had plenty of "I've fallen and I can't get up" stuff. Lots and lots of those. But we'd also get a fair amount of real calls that were actual emergencies. So all in all, working the crappy calls was worth getting a decent one a couple times a shift.
Right now my certification has run out and so I can't really do much of anything unless I re-take the class (I'm also past the renewal date
🙁), which I probably won't do. It's very frustrating to volunteer in the hospital and not be able to do much of anything, when just a few years ago I was doing CPR on patients and running real calls.
The conclusion I'm trying to get at is take the class if you're interested in using the certification in one way or another (volunteer EMS or paid ER tech/ambulance company) but don't if it's just something to list on your EC list. It's not worth the money or the time. Like was said before, you can learn all the stuff covered in the course just by reading a textbook and practicing taking vitals on your friends. But being certified and being able to work in a medical setting and DO THINGS is totally worth taking the class.