I get this all time time. Professionally I'm a social worker, and I work with extremely high needs kids. When the kids are only on track for me, its because I'm big, not because I'm skilled and was once one of these kids. People automatically assume I'm not very bright, but then I hand them my resume; graduated with an honours degree, highest average out of the entire program. So people can think what they want, it usually only takes 30 seconds of conversation to convince them how far off they are