Many social issues get tons of attention for various reasons. For example, anti-smoking campaigns get funding from related philanthropic organizations like Cancer related charities. But without people with money who care about an issue, social change, let alone social awareness, don't happen easily. Issues related to children seem to be at the bottom of that financing, which is a very big shame. But, beyond "children should represent children's issues", the way that those who do fund these campaigns go about it is very interesting and up for question.
Instead I'll share with you some social advertisements that were featured in different parts of the world that put children in the focus of the frame. You be the judge if they are effective or not, and whether the use of children in them is acceptable, tasteful, etc.