Getting rid of plaque on teeth?

Correct me if im wrong but i BELIEVE the white parts on my teeth are plaque...and im trying to figure out how to get rid of it. I floss 2 times a day, brush 3, and use mouthwash once (which is better than what alot of people do). However, i still seem to have this white plaque on a few of my teeth. One possible thing could be lack of calcium. I heard that makes teeth stronger and i dont like milk (except in cereal) so i could be lacking in that but i dont know. The plaque is mostly on my side teeth where u bite into food (on the top of the bottom ones and the bottom of the top ones) but now it is starting to develop in the front ones too :/ any advice? Thanks!