Clara is very knowledgeable about the world (as she knows about immersion therapy), and enjoys living a 'minimalist-chic' life. She seems to be rich as she owns a motor-home that can be used for going camping. She's a supportive friend to Annie and Pony. She’s also an honest girl, as she admits to almost everything she was involved in.
She appears to have a secret crush on Gerry because in Game Horse she explains to him "Gerry, I've always loved you", which made him confused.
In School Dance, she comments that he looks great in his formal suit, though she quickly covers her mouth, presumably having not intended to say that out loud.
In Pony Car, it is revealed that Gerry reciprocates her feelings for him. She tells him that she'd love to dance with him.
She and Annie have had a close relationship since almost the beginning of the show. It's shown that they mean a lot to each other. And they're mostly seen walking out of school, or just hanging out together.
In Clara Time, Annie thinks that Clara is avoiding her and Pony. Which Clara admits isn't true and that she has just been busy. She's also amazed at all the effort they put into making a huge chess game in the park.
In Pony Car, her cousin Barrington invites her to a party. She's scared to go by herself, so she tells Annie to promise she'll come to the party. Which confirms she feels safe around her. And Annie keeps making sure she keeps her promise, and would do anything to keep it throughout the episode.
In Horse on a Hot Tin Roof, she gets jealous and upset because she didn't get the main part as Little Mama to Annie. But at the end, she tells Annie that she's really proud of her. And Annie tells her she's "the best, ordinary girl with no lines, ever". And they hug.
↑her mother is addressed as Mrs. Bornstein at the start of Dad's Speech when she tells Clara's class about how she contributes to video game development