The best tools for rewarding kids on the potty are skittles and m&ms.  I have found (being a past preschool teacher), that kids love these special treats.  They love choosing the color of their reward as well and showing it off!  I am all for it, I plan on using them when I potty train my son!

I tried candy rewards for my munchkin, but ended up with a very hyper munchkin.  I say if it works try it.  If you don't want to go that route, what we ended up doing was going to the dollar store and buying about 20 toddler safe toys (20 dollars).  Everytime she went poopy on the potty, she got a toy.  Evenutally, it went down to less frequent hands on rewards and more other rewards, such as going out and playing bubbles for 10 minutes and such.

We moved right into big girl panties as well.

We use the little tiny boxes of raisins for my 1-1/2 yr.old granddaughter.  That is the only time she gets the raisina is when she sits on the potty.  She loves them, they don't make her hyper and they are a good source of extra iron, plus they aren't filling so that she still has her nutritious snacks and meals.

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We put a glass jar of m&m's in the bathroom, so they saw it every time they did anything in there.  They would get ONE for a pee pee and TWO for a poop.  A very big deal to them.  They got to pick the color.

They will only be potty trained when they want to.  Especially if you make a huge deal out of it.   

 I occaisionally use puffs as a bribe to get her on the potty in the first place! but not as a rule.

We use star stickers as a reward for actually going on the potty and she has a big space picture taped on the fridge that she adds stars or planets to ( she gets a planet when she asks to go and produces something!). She loves her chart!  

I personally am not a fan of using sweets or food as any kind of reward.  I like the sticker chart approach.  Use a chart and give a sticker or star each time they use the potty.  After 5 (for example) stars they get some kind of reward.  Maybe a toy at the next trip to the grocery store, etc.

Good luck!

I used M&Ms. I taught my kids to wash their hands after going potty before they get the M7M so they were rewarded for going potty but they also learned to wash hands. I hav also used the cheese goldfish for rewards.

I used M&M's as well with both of my kids.  I kept them in a large glass container right in the bathroom (so they could see it and be reminded of what they really wanted!) and taught them that one piece was for peeing and 2 pieces were for pooping.  They had to wash their hands first and then I would hand them their treat(s).  I also integrated the use of a timer when they were first starting out and set it for 20 minutes (gradually working up to an hour)...if after each alotted time, they were successful in using the potty, they would get the treat. 

I say to just give it a shot and see if this type of reward method works for you.  You know that it's becoming less effective when they're constantly going (like every 5 minutes) because they've realized that a little tinkle here and there might be getting them an M & M.   I would put Cheerios or Apple Jacks in the toilet for my son and have him do target practice.  This was fun for him and really required him to have a "full bladder" instead of the little trips here and there that he started doing in order to get the candy! 

 This whole process probably took a couple of weeks for each kid.  My last trick was to make a Potty Chart (which I have saved on my computer so if anyone wants it, e-mail me) and use stickers.  My kids LOVE stickers...if yours does too, this is another trick that might work! 

If my son liked something like M&Ms, I would've tried them in a heartbeat!!!  Instead, I promised my animal-crazy 3-year-old that we would go to Target and get a new elephant.  So when he finally went poop in the toilet, we made a big to-do, went to Target for dinner (he loves their hot dogs and mac & cheese) and bought his new toy.  Then, for the next three days, he went in his pull-up.  I threatened to take the elephant away, which worked for two days or so, then we had 3-4 days of going in the pull-up again (and yes, the elephant was kissed goodbye and put away by him).  He ended up having to give up the elephant twice - the message seems to have gotten across now.  Pooping outside of the home (in a toilet) took another new toy....so far, it's been almost two weeks and I've never had to take it away.