Either that or part of the thief gang. She kinda lead the detective boys right to the body after all. i also find it suspicious that she was exactly ten years older than kobayashi sensei and the murder happened ten years ago. Maybe she was a teacher in training during the time of the robbery and allowed the robber to use the school as a hiding place, but they still can't find the money the dead guy hid so she's using the detective boys, who've become kinda famous by now, to solve the mystery.
Wow. That's cool and a good point. She is definitely an odd one though.
I feel like Wakasa-sensei is part of the black organization. Not only is she too clumsy but that look she had in the last panel made me feel that way.