There are lots of good posts about goals, motivation, and conflict, including an excellent one on today's Adventures in Children's Publishing blog.
As much as I enjoy discovering these ideas, my fallback is a strategy I used in the classroom during reading instruction: Somebody-Wanted-But-So (SWBS)*. In my version, the goal is present tense:
1. Somebody (a character)
2. Wants (has a goal)
3. But (something stands in the way)
4. So (s/he tries to overcome it)
It's simple, succinct, and flexible; you can apply it to an entire book, or break it down by chapter and/or scene. When applied to each character, it helps summarize the overall conflicts within a story.
Take the Big Bad Wolf. He wants to eat the Little Pigs, but they won't let him in, so he blows down their houses and gobbles them up. When he can't level the brick house, he tries to sneak in via the chimney, only to fall into a vat of boiling water.
Why does he fail? Because the smartest of the pigs has his own SWBS: he wants to thrive in a hostile world, so he builds a secure house, but when the wolf finds another way in, the pig figures out a way to thwart him.
THE WIZARD OF OZ is a great example as well. The characters are memorable not just for their personalities, but because each one has a clearly defined SWBS.
For my own story, I used this approach from page one. My MC wants to meet the Mermaid Queen, but her parents refuse to bring her along on their monthly visits, so she devises a plan to sneak aboard their boat with the help of a dazzling jewel, a scheme that backfires in ways she never imagined.
So there you have it: goal, motivation, conflict, and resolution, all in an easy-to-use formula.
*This strategy is attributed to MacOn, Bewell & Vogt, 1991. For a template of SWBS, go to
http://wvde.state.wv.us/strategybank/Somebody-Wanted-But-So.html and click on the chart link.