Help the parents deal with the decision of buying a book and also with questions that the child might ask or that the parents might want to raise as the child is reading through the book.
Publish a short guide for parents about the book. They can peruse it in the store to help them decide on buying the book and take it home for free with the book they bought to help them as their child reads it.
Teach kids business and entrepreneurship in a fun way.
A business selling “franchise” kits to parents and their kids. These include teaching materials on how to build the business: basic definitions, functions, how to start, how to plan, marketing materials and principles, etc. Different “franchises” can be bought, for particular age groups and interests.
Your kids are begging you for a pet. It would be good to know in advance what it takes to have one.
A guide that shows you – separately for each animal – what it takes to have one at home. Details such as eating habits, smells, typical life span, amount, and detail of care needed, what can you do if it’s not a good fit for your family after all, what to do when going on a trip, etc.
Although there are some sources of information for parents on a movie’s suitability for a certain aged child, these are quite dry and sometimes it’s hard to decide without watching the film.
A website where each movie is graded by parents who saw it. Each such review should be as contextual as possible, giving the reader the points pro and contra, the personal experience and age group suitability based on their child. This way the reader will have a better filter to apply it to their own child’s age and personality.
Today, most children already want to have an email account (or other messaging systems) before the providers allow them to (before they turn 13.) A method that allows them to start doing so at younger ages and also teaches them best practices might help.
The current system could be augmented with an option for younger kids, where every message first goes through their parent or guardian. At a younger age, the filtering by a parent would probably be less of a problem than when they are teenagers, especially if the service provider mandates it for younger ages. The parent could then see how the child is using the messaging system, block a message if it’s a problematic one, or let it be delivered if it’s ok. Then talk to the child to explain what was wrong with it, so they can learn how to use the system well and what to beware of.