Plagiarism

Plagiarism is when someone copy and paste or copy from a book a text or anything else. I think plagiarism is not allowed in school because when you copy from something you don't really learn and if the teacher finds out you have to do it again. I never did plagiarism but once one of my friend did it in a science project and when the teacher find out she add to do all her project and she was loosing mark's.