Expressive Shirt - Her dress, which is usually a plain purple one, has pictures that are always related to the episode's subject. Arnold even notices this pattern after they had a field trip in his Digestive System.
It Runs in the Family - Has a HUGE bevvy of various aunts, uncles, and cousins, who are sometimes famous people such as "Uncle Edison" in the electricity episode, "Uncle Frank Lloyd" in the construction episode, and "Uncle Poseidon" in the salmon episode.
Multiple Choice Past - She's been a lot of places. She was once a Shakespearean actornote Light episode, spent 6 summers on the Rodeo circuitnote Construction episode, took a summer to learn how to announce a baseball gamenote Baseball episode, formed and toured with the band "The Frizzlettes" with a now-famous rock starnote Molecule episode, and many others. To quote The Friz herself:
"You'd be surprised what we teachers do over the summer break."
OOC Is Serious Business - One time during the desert episode he actually suggested to go on a field trip to help understand about desert animals (Phoebe was wondering how to help them out). The reaction from the rest of the class?
"Arnold, are you serious?"
Only Sane Man - It may be presented as cowardice, but, really, he is more than justified in being completely and utterly scared stiff of the sort of thing that happens on the average class trip.
Hidden Depths - As early as the digestion episode, demonstrates a Big Brother Instinct towards his classmates (he went out of his way to track down and retrieve Wanda) and was revealed in "Gets Swamped" to be very accomplished at debate.
Magic Skirt - Dorothy Ann always wears a pleated miniskirt which stays down no matter what.
Or not. In season 1, episode 12 "Gets Ants in its Pants", Dorothy Ann gets a very brief Panty Shot when she jumps into a hole. She has another in episode 41 "Cracks A Yolk" when a gust of wind blows her skirt upwards, revealing her white panties.
Dogged Nice Girl - Downplayed. It's heavily implied in "The Busasaurus" and "Goes Cellular" that Phoebe has a crush on Arnold, but at the ends of both episodes, despite the fact she helped him get a dinosaur egg back and tried to help him look less orange, he largely ignores her and goes back to focusing on Wanda.
Huge Schoolgirl - Despite the kids generally being drawn at similar heights, there have been times where she appeared taller than the others and towered over Wanda (such as in "In a Pickle" and "Revving Up").
Suddenly Voiced - In some of the computer games based on the show, Liz is suddenly able to talk, often serving as an in-game helper to the player. To be fair though in the majority of cases she only talks to the player and never to the class themselves.
The Sociopath - Could go along with Jerkass, but Janet has shown her sociopathic tendencies, ranging from her obsession with feeding butterflies to a "bog beast," her constant irritability, annoyance, impatience, and aggression towards the class (most often Phoebe), her obvious irritation with being bored ("Gets A Bright Idea"), and that she seems to have no problem with lying or cheating ("Makes A Stink"). The only person she seems to have some empathy for is Arnold, but even then, she has no problem manipulating him as long as she gets what she wants.