1. You can deal with heavy subjects, but sometimes these are not happening to the main character. Especially in historical fiction books where the history is known (such as Nazi concentration camps or slavery in the United States), you don't want to ignore these grim historical happenings. But you can either tone down the reality, or minor characters can have the tougher role. The main character is not the slave or the refugee, for example.
In my middle-grade novel, Finding My Place, the main character Anna has a lot of tragedy happen during the book, set in 1863 in Vicksburg, MS--her ma dies; her pa is at war; her family has to live in a cave while the city is being shelled. But all in all, these things are happening around her. She is affected by them; but for example, she does not get wounded by a shell. She is not a slave.
Kids are smart, so you can't pretend like real life can not be terrible, but you can tone it down.
2. Life can be grim. It has been. But it can also be comical and happy.
The other thing you can do is put in some lighthearted scenes or a funny character. Your main character can also be funny at times. Look at the middle-grade novel, Holes. Again, this deals with some heavy subjects--basically children being driven to work under terrible conditions at a juvenile detention camp. But parts of the book are comical. I mean even the main character's name--Stanley Yelnats is a bit silly. If Louis Sachar would have made everything about this book as emotional or heavy as the topic could be, the book might not have been as popular with the middle-grade audience. Most children's movies have a character that is for comic relief--Olaf in Frozen or Eddie Murphy's dragon in Mulan. It works. So think about adding a little comedy in the midst of the tragedy.
3. Read other authors and see how they do it.
If you still aren't sure what to do, take Stephen King's advice from his book, On Writing: "You have to read widely, constantly refining (and redefining) your own work as you do so. If you don’t have time to read, you don’t have the time (or the tools) to write.” Talk to a librarian; read middle-grade reading blogs; check out state recommended reading lists--there are ways to find books that deal with grim subjects, and figure out how these successful authors deal with a young audience but a serious subject. Learn from them, and then transfer these ideas to your own work.
So have you ever read a book for 12 or under with a serious subject? How did you feel the author handled this problem? Are you facing this in your own writing? We'd love to hear about your experiences.
