Short answer: It depends.
First, allow me to mention that children (11-12 years old and up) are often the best agents. They are inquisitive and often search in places that adults overlook.
So how about sending in a troupe of eleven year old agents? Not so fast. First, any group of youngsters needs at least one adult to go with. This is to provide a small dose of guidance and adult judgment. Would taking out all the light bulbs lead to a clue? How about taking down the wallpaper? Probably not. Most adults would realize that (I hope)? Kids, not necessarily. So for birthday parties or sports teams, the youngest age would be 11-12 with one or two adults accompanying.
What about children younger than that? Kids ages 6+ can often help solve the mystery, but they need to be with adults and older children because they won’t be able to do it on their own. So young children are fine to bring as long as they’re with a family, but a group of nine 6 year olds along with mom or dad wouldn’t work so well.
What about very little children or infants? We don’t recommend that you bring them since they aren’t able to understand the mystery and so they can’t really get involved. And an infant tends to detract somewhat from the setting (I mean, would you really bring a baby in a car seat on your attempt to save the city. . .) That said, at Save Milwaukee you’re never locked in a room, so you can always go out if a child needs attention. We leave the decision on whether to bring an infant up to you.
Finally, what about teens? Teens are terrific agents, but alas can also sometimes use a bit of adult guidance and supervision (i.e. smashing things is not the appropriate way to save our town. . .) Teens are welcome but we ask that an adult either participate in the mission or at least hang around while they’re solving their detective challenge.