Now as Jared said years ago, Dorothy is American on a poor farm just barely getting by; while Alice is British, in a household who has a nursemaid and kittens and therefore fine living. Now I admit I have never taken classes that teach etiquette or such manners, but I have seen the different ways in which things are demonstrated and you can pick up a few things if you pay attention...
Both girls know manners and how to address people, but in similar actions they show differences.
STANDINGDorothy, being poor, wouldn't think too highly of herself, so she would probably have her hands out in front, sometimes holding them together. She wouldn't quite be in the right time or character to put her hands in her pockets, maybe she would but not constantly or by means of being difficult. Also, being a bit easier of mood, Dorothy would feel at ease with her legs a bit apart. As those who have read "Through the Looking Glass", will remember the Red Queen instructing Alice to
"Look up, speak nicely and don't twiddle your fingers all the time . . . open your mouth a little wider when you speak and always say 'your Majesty' . . . turn out your toes as you walk -"And Alice would have been instructed to hold her hands behind her back when reciting lessons in class.
SITTINGI could be wrong, but farm people—despite all the hard work—still manage a free and easy attitude and one of the ways of expressing that lifestyle is the way you sit. Slouching is not recommended or good for health, but it can show eagerness or a more interested way of viewing things. Sometimes you can even have a foot sticking out or swaying about, as Dorothy shows. Notice how I gave Dorothy's arms more than one position, so that you can choose to see her either holding her hands together in her lap or by her sides.
Alice, however, is not brought up to sit likewise. Straight backs, hands tidy and neatly placed on the lap, knees and feet together, all in a chair. Now there's more than one way to sit: up (on a chair or something firm) and down (on the ground). Dorothy is cross-legged and Alice brings her feet out to the one side. Drawing this bit of the girls sitting on the ground was a little tricky, but their characters showed through after some thought.
CURTSEYINGIn one episode of The Nanny where company is expected, Gracie and Maggie Sheffield curtsey, when their father instructs them "No, no. Straight backs." (To which his son says "I'm getting the disturbing feeling he's done that before.") Since Mr Sheffield is British, this simple rule would appropriately be suited to Alice. Now while far from royal, Dorothy does have manners and bows to Royalty (even if its Oz-related). The difference in their bowing can also apply to their hands: Dorothy grasps her dress almost completely in her hands, while Alice uses only a few of her fingers (and may or may not hold out her pinky finger).
CRYINGNow, shedding tears is natural for girls (and guys can do it too, whether we deny it or not, some of us just look cool trying not to show our tears). I'm no expert in the difference of how girls cry, but it's not that hard to figure out if you know the characters well enough. Dorothy is allowed to express her emotions and Alice is brought up to be tidy and proper, but I'm sure both girls would at least have a handkerchief ready in their pockets when needed. In trying to show the differences between these two crying, my guess is that Dorothy would hide her face in her hands, or cross her arms around her folded-up knees Alice would not be allowed to make such a mess and therefore be expected to cry into a handkerchief (or apron as you can see), or most likely have one handy to wipe away her tears.
It should also be noted that the emotions of British are usually more subdued than American or other countries, they would cry but just not necessarily think it a big deal (and at times find it a bit much, but I'm merely going by how I've seen it portrayed in comedies).
Now as I said before, I've gone back to the books version. Meaning I have avoided the film treatments. Nothing is wrong with them, but it can get tiring. Whenever something, show or book, includes both Alice and Oz, they always seem to follow either the book or Disney cartoon of Alice and with Dorothy they go for . . . you guessed it, MGM. Have a look at these scans from "the Jolly Pocket Postman" . . .