This is a perfect example of a movie for kids that is appropriate and still fun. There are three other Clubhouse Detective movies with these kids. I saw this one on HBO a long time ago.
The kids have to save their clubhouse from being taken over by the neighbors and become embroiled in a treasure hunt to earn money. The kids are a lot of fun to watch on screen. The rivalry between them and the neighbors is cute, it will probably remind parents of the one kid in school that acted the same way. It's not scary at all for anyone older than five.
This is a good one to watch with the family, no annoying songs and it's not sickeningly sweet, great for movie night.