Number 1 - Avoid flashbacks and too much back-story in your first chapter. This statement was confirmed by Abigail Samoun from Red Fox Literary Agency, during my critique at the latest writers workshop I attended. I also read it in "Hooked," by Les Edgerton, and "Blockbuster Plots," by Martha Alderson.
Number 2 - The Crisis vs. Climax - Yup, there is a big difference. According to Martha Alderson's book, "Blockbuster Plots," the crisis occurs a little more then half-way through the book. It is dramatic place in the plot, a possible epiphany for the MC to see themselves clearly. "It is the dark night of the soul," says Alderson. The Climax is the highest point in book where the MC shows the reader they have truly changed and who they really are inside.
Number 3 - Minimize the Passive Voice - Avoid sentences using some of these key words: is, was, will be, is being, going to be. 'Were' is active, while 'was being' is passive. I really liked how one person put it though in a person on a forum named tedster gave his advice.
passive: "The beanstalk was climbed by Jack."
ACTIVE: "Jack climbed the beanstalk."
It's best to minimize passive sentences, but still use them intentionally in order to soften the voice and vary the pacing. In the hands of a good writer, the occasional passive sentence can be powerful, colorful and effective. But the term "passive sentence" is not about the difference between hard hitting and washed out. It's about grammar.
Number 4 - Story Worthy vs. Surface Problem - Understanding the difference between story worthy problem and surface problem in your novel has stumped me this past month. Les Edgerton, author of "Hooked," spends a lot of time in his book helping writers work through this. The surface problem is the active surface problem your MC needs to solve. The story worthy problem is the underlying emotional issue your MC is struggling with, it is slowly revealed through the plot. Both the main surface problem and the story worthy problem are solved in the last scene of the book. They are connected, but different.
Number 5 - Scene vs. Summary - This point was best described by Martha Alderson in "Blockbuster Plots." Scenes are moment by moment action. They are important plot points that require to be right there with the characters. The summary is narrative of events that don't need extra explanation. It can be really tiring for a reader to constantly be in scenes, they need summary breathers.
Number 6 - It's All About the Tension - The king of teaching tension is Donald Maass, author of "Writing the Breakout Novel." YA novels must be written in a way that makes the reader want to turn the page. Our youth have so many distractions around them that if you don't have tension in your story, and a MC that a teen can relate to and care about, then they won't spend their time reading the book.