I'll give you my $0.02 on the subject, but remember, this is only me, and there are many other perspectives out there.
Should you go to graduate school: The easy answer is yes, given that the question is so broad. Graduate school is where you actually become a master in certain techniques, learn quite a lot in your field of interested, and get to use that wonderful brain of yours to create, expand, and explore in new territory.
However, the world is not an ideal place, and it is highly unlikely that 100% of your graduate school experience is going to be happy-go-lucky and steadily continuing without ever doubting your decision. Here are the points that I find most important in deciding whether to go to graduate school:
- First - can you get in? Is your GPA above a 3.0 or 3.2? If not, you may find it difficult to get into good programs. A strong GRE score, along with exceptional letters of recommendation can get you in, with an "lower" or "average" GPA. Really though - if you're considering graduate school, you probably can get in to many of them.
- Masters or PhD? Very few programs pay you to get a masters, but many pay you to get a PhD. The national average is around 24-26k a year, which isn't bad. If you are going to medical school, you need to pay for it yourself, unless you can get some really fantastic fellowships and scholarships - but that isn't my field.
- Are you passionate about anything academically? When I started graduate school (only 4 months in so far) I had the wrong idea that, really, I could only get into the "hard" sciences, and that "soft" sciences aren't worth anything. Hard sciences are chemistry, biochemistry, mathematics, engineering, etc. While "soft" are sociology, psychology, ethnobotany, etc. If you are passionate about learning ANYTHING at all, there is a program out there for you. Search, search, search. Just recently I met someone who was doing research on how Maya interact with plants. He's written a few books and travelled all over the world. He retired a few years ago, but was taking students - I would have absolutely died to do this!
- Do you care what happens after graduate school? For me, I don't give a damn. I'm currently in a Plant Biology program, but once I fulfill my PhD, I have no plans in continuing on to post-doc work, or becoming a professor. I would love to teach, but the details are hazy. If you really want to go on after, and become a post-doc, or become a professor, you really need to be competitive - which means doing "out-of-the-box" research, and literally devoting your life to the work. You will need to spend a bare minimum of 40 hours a week in lab.
- Do you like to travel? Some programs differ in this respect, but in the hard (and some soft) sciences, you're travel will be limited, and your new school will become a pretty heavy shackle on your leg. For me, I plan on definitely taking months off in the future, but it's not always possible (or safe) to do so. It really depends on your professor.
- Can you deal with people telling you what to do? Some labs also differ in this regard. Many professors will tell you exactly what they want you to do. They need to keep their record of publications of high quality and good quantity, so they may pressure their students to push projects. This can be heavily taxing, and may not allow the graduate student "breathing room". I'm, again, lucky as I feel I can do whatever I want, in the realm of plant biology.
- The biggest of them all: do you really want to give up these years of your life? I'll be brutally honest; graduate school will become your life if you're going to succeed, and get your degree. This pertains more-so to PhD but a masters can be just as involved. Generally a PhD is 4-7 years long, which translates to years of 22-29 years of age. That's a lot of time, and at the prime of your life. If you have a professor that is lenient, you can take plenty of time off and explore the world if you'd like. Others aren't so lucky. Make sure you get into a program and in a group that is nurturing to you as an individual person, not just someone to do work.
P.S. Did I mention you'll probably get paid for learning? Pretty sweet deal.
For me, I don't really stress the future, nor the present. When it gets bad I go on vacations, and when its good I absorb it like a sponge. I don't really care what happens after school, so the pressure to do extraordinarily well isn't something on my mind all the time. I'm motivated, but I'm not stressed. If I really cared about getting a tenure track position and an amazing post-doc position somewhere, I wouldn't be writing this blog - I would be reading academic journals till I drop.
I hope this helps answer some questions out there.