OMG, I think you might be talking about 'The Mystery Files of Shelby Woo'. 🚨 It's definitely got the mystery-solving kids vibe and if I remember right, there was an episode with a haunted museum. Hope this helps!

Oh man, I remember watching bits of this as a kid. But seriously it feels like a fever dream now since I can't find anything substantial. Anyone have leads on more clips or episodes??