NOTE: This unit serves as an INTRODUCTION to number theory to high school students. Formal proofs are not included in this plan. This unit only touches a couple topics in number theory in the hopes of 1) students to persuade mathematics as their major or 2) realize the importance of number theory, especially how it relates to cryptography. If you are teaching number theory through Discrete Math, Applied Math, or any other courses that has number theory as a unit, this unit is right for you! Pl