How to make a girl think you can do better then her or act like u don't care with out being rude?

Theirs this girl and she is high manteins like i kno i can do better then her but she dosent think so i dont want her to date me just quit actin like shes better then me so how do i push her off and act like i can do better then her snd like i dont care with out being rude btw we are freshman in highschool