Hi Danielle-
Welcome to the forum! What wonderful ideas you have written here. I agree that kids are so observant! Often missing kids are enrolled in school, especially in a custody dispute/parental kidnapping. The child maybe using a different name than the one on the missing child's poster but kids are excellent at observing things that are not quite right.
I always show my children the ADVO missing child picture that arrives on the mass coupon mailer each week. A missing child could be playing in the same neighborhood, local park, or be part of a boy/girl scout group or other child/teen club.
I would love to here what other people do to help missing children in there area.
Have a blessed day!