Hey Tori, This is an old recipe. Probably something your grandma used in her days...haha
Mix 2 tbsp baking soda with enough hydrogen peroxide so that it gets to a paste like consistency. Use like a normal toothpaste 1x a week and voila, whiter teeth. You can add some mint extract if you have some to mask some of the salty taste off. Remember this is not safe to swallow and to use once a week only :)
A little extra virgin olive oil on cotton balls also work quite well. And I saw on the Tyra Show that strawberries are good too. But with the strawberry you have to brush afterwards because of the sugar.