- Pays well
- You have a job right on campus, which is awesome (less travelling)
- Mad respect, yo -- become a role model
- Learn how to teach and become a more personable person, which helps in many aspects of life
- Teaching reinforces your knowledge
- Get to know faculty better
- Undergrads make better TAs than grad students (if you're awesome)

TAing has helped me quite a bit, not only financially, but educationally and personally.  I highly recommend it to qualified people.

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You'd think a thousand miles would be enough,
I guess I'll keep walking.

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All of my TAs are either doing their Masters or PhD. I'd wait until grad school.

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Yeah, most of mine are graduate students also. I've had 1 or 2 that were in their 4th year.

I'm planning to take 5 years because there's too many courses to do in 4 years, so I figured, why not do this? I also have some friends in my current year who are thinking of TAing. I'll wait and see.