I know, I know, I saw WitchHatBunny's Animal Jam Blog, and she changed her username.
Here is how you change your Animal Jam username, since, well, she wouldn't tell us.
Animal Jam HQ is only capable of changing your username, so email them at firstname.lastname@example.org like this:
Hello Animal Jam! I would like to change my username:
My old username is: [your old username here]
My parent email is: [your parent's email for animal jam here]
My 4 unique choices for a new username are: [4 unique choices here]
If you have a membership on your Animal Jam account, type the above, except for the words in brackets, and the below:
The full name billed under the membership is: [full name billed here]
Full billing address: [full billing address here]
The last 4 digits of the credit card used are: [last 4 digits of the credit card only if you used a credit card or visa for the membership.]
You should get an email back from them telling you your new username.