Here are some books on writing that I have found especially helpful.
The First Five Pages by Noah Lukeman,
How to Write a Breakout Novel by Donald Maas
How to Write Science-Fiction and Fantasy by Orson Scott Card
Plot & Structure: (Techniques And Exercises For Crafting A Plot That Grips Readers From Start To Finish) by James Scott Bell
Elements of Fiction Writing – Characters & Viewpoint by Orson Scott Card
Writing for kids
The Writer’s Guide to Crafting Stories for Children by Nancy Lamb