storybook cassette help, please!

Aloha! I hope everyone is doing well. I'm looking for a storybook cassette or read-along that I listened to a lot back in the ninety's. I'm not sure what it was called. I remember that it was about a girl named Gwen. She's having trouble in school and making friends. She goes to her grandmother's house one day and her grandmother tells her she's a real witch-that they're all witches. And Gwen starts to experiment with magic and stuff. I used to love it! If anyone can help me out with this, I'd really appreciate it.
Thanks!