The sad truth is kids are stupid and cruel. Most of the people laughing are just as insecure as you and probably have zero malice towards you. They are just afraid of being the one being laughed at so they laugh at you to try to avoid it. I know it doesn't really help at the time. It's just a hard time of life for everyone, especially someone who has something about them that makes them stand out I know it's sometimes very hard to stand up for yourself in those situations. As an adult I have a zero tolerance rule for anyone laughing at me not with me about my stutter but adults are way more afraid of confrontation. Especially when they know they are in the wrong. The only thing you can do is forcus on your real friends. In early high school I found a good group of mates and gained a bit of safety in numbers.