I stand at least a head taller than the tallest one, and he and his cousin are Purple Belts. The youngest one is about elbow high on me, and is still a White Belt. I an a First Degree Brown Belt, just below Black.
I think it's just inexperience on their part, and maybe just pushing the boundaries with the only female in class. I tend to be the "tough" teacher and insist on proper manners and etiquette, which they tend to "forget."
"Anything unattempted remains impossible."