At the start of "Revolting Children", Hortensia's right sock is pulled up and her left sock is down. However once she exits the school building, her right sock is down and her left sock is pulled up.
Early in the movie, Miss Trunchbull is referenced as having competed at the Olympics after having also been the 1959 English champion in Women's hammer throw. This was not an Olympic event until 2000, making it unlikely Agatha Trunchbull competed at that level. Given the character, however, it might be presumed that it was all fabricated.
Despite the fact that Trunchbull despises pigtails (to the point she hurls Amanda Thripp out of the schoolyard by them), there are a few girls who sport the hairstyle.