In today's market, writing an overtly didactic children's story for the trade market is usually a kiss of death for the manuscript.
Avoiding didactic writing or themes might be one of the hardest concepts when beginning to write for children. I get it; our adult mind -- either consciously or unconsciously -- wants to share what we've learned and what we know. We may feel that children of today need a nudge in the right moral direction. Or if we are of a certain age and grew up when more teaching-heavy stories were the norm, it could feel familiar and natural to write a story with a strong message.
However, I want you to succeed as a writer of children's books and these type of stories will likely not be acquired in today's market because:
1. a didactic story reflects the writer's ideology and unique perspective instead of allowing the reader to bring their own perspective to the story
2. a didactic story narrows the scope of the story to only the writer's experience instead of opening the reader to new worlds
3. a didactic story often has only one layer -- the moral or teaching -- instead of offering many layers for self-understanding and growth.
Great literature doesn’t tell you what to think or how to feel. It simply creates the space for those thoughts to happen on their own."
-- Oprah Winfrey