How do you tell your parents your in love without them thinking its just a fling?

Well, if you are a girl, start talking to your mom about how she knew she was in love and stuff like that. She may ask you if you have a crush, and there is your chance. If not, say, "Mom i have something to tell you. I kinda have a crush." She might understand what you mean. When she asks who, say the name and why. If you think he likes you, tell her. Maybe you can go on a date.