legally...no. illegally...yes. you can try making a business, instead.

Its hard to teach in China (impossible anywhere else) without a bachelor's degree as its a requirement for getting a working visa the legal way.  I suggest if you want to come to China that you come as a student and study Chinese for a year and then you can see what opportunities may lie ahead here. 

Legally you can't, but that hasn't stopped thousands of foreigners from doing it anyway.  There is a small risk of getting caught, especially in the larger known English centers, high schools and universities, but if you work in a small kindergarten or do 1 on 1's with the neighbors kids or college students, no one will even care to ask.  Since you are here for the travel and experience, I wouldn't be so worried, worse comes to worse, they just send you packing.  Pretty much all schools here will hire you automatically if you are white and young. Some will ask if you have a degree, but I can't remember a situation where they wanted to see it.

Legally - NO!

However, if you do manage to get a job, please pass on some details... I'd love to inform the PSB so you can get kicked out of the country (and fined!)

Non-qualified 'teachers makes our pay plummet!!! Thanks guys and girls....

You don't meet the requirements, but don't let that stop you. Someone will offer you illegal work and cheat you because you will have no legal recourse as an illegal alien.

When they cheat and abuse you, you can post complaints and ask for help, which no one can provide.

You choose.

No, you won't be able to find (legal) work. Please leave.

If you put in the hard yards back in Canada with a company that has a office in China an build up your experince and knowledge you can work here. The chances of that happening is slim 99% chance of not getting it. 

But since you are only 21 I will give you the best advice no one here has given you. 

You're from Canada apply for a working holiday visa to Hong Kong, Taiwan, Japan and 20 odd different other countries. You can teach legally for short periods of time in Taiwan and Japan or pick up odd jobs in Hong Kong.

all what have been said here is true. anyway, just come and give it a shot, if u didn't like it in here then, it's up to u stay or leave. best luck

It's very difficult. Your age is still a factor to consider as well. To work legally you need a Z visa which I believe, correct me if I am wrong aren't issued under the age of 24 or so years old. You can get a different visa but that's not really such a good idea. If your caught you could be in a hole lot of sh*t.

The jobs available to you will be the sort which, all the other qualified teachers disregard due to, contract conditions, office hours, teaching hours, pay, accommodation allowances, health insurance and so on. Also more than likely a 3rd or even 4th Tier city.

You could try completing a Tefl or even better a Celta. Celta is a respected qualification and holds more punch than a tefl which you can complete in a matter of hours.  Most schools now require a CELTA as they know any Tom, Dick or Harry can complete a tefl while pissing it up on beach somewhere.

I know some teacher's which have completed a CELTA or even DELTA and do not hold a degree and they are by far, much better teachers than fresh grads living it up.

Its is possible, give it a go and I wish you all the best. But don't get sucked in at the first opportunity. Have a look around and judge what's best for you.