Get to know your intended audience. Read a bit about them, and most importantly spend time with the kids. If you do not have some of your own, pal around with nieces, nephews, cousins, etc. This is by far the best way to learn how they think, how best to relate, and so forth.
Step2
Learn the material. Read items similar to those you wish to write. Also read as much as you can in general. This step is universal to all writing. The more you read, the better you will write.
Step3
Begin your project. Now that you have the basics down it is time to get to the business at hand. Decide what you wish to write. Set up some basic ideas and plans. This can be anything from notes in your head, to a full blown outline. Go with what works for your style of creativity.
Step4
When you are finished, let your work cool for a few days. Go back and revise/polish. You may want to test your work as you go, by having any available kids read/comment on it.
Tips & Warnings
When writing nonfiction verify your facts well. Kids may not admit it, but they do take ot heart things they read so do not mislead!
Writing is hard work. Do not lose heart. Stick with it!
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