Have you ever seen a celebrity look alike and who did she/he look like?

Theres this boy at my school whos in 8th grade(im in 7th grade) looks just like justin bieber. when i first saw him i thought that was him(idk why) and almost threw my shoe at him. theres this other boy in my grade who looks exactly like bruno mars. lol if my friend saw him who goes to another school he would of sh*t his pants.