I know what you are talking abou; kids can be so mean. I was always fine about my body (actually I never thought about it, because it was just me) but then when I entered middle school people made fun of me and I felt really depressed. I lost abunch of weight between 8th and 9th grade before highschool so I don't know if thats why or what but I like Highschool a lot better. Just remember when kids make fun of you its because they have a problem, if they were self-confident they wouldn't feel the need to put others down so in other words they feel bad about themselves too. It might be apperance (you'd be suprised at how thin someone can be and still feel fat)or it could be their parents are mean to them or something like that. Just hang in there and you can do it!