Sometimes when writing, I run into a brick wall in search of a better word or emotion, or want to check how well my writing will read.  Below are a list of resources that I use for those occasions.

Vocabulary Lists
It is said that most adults read at an 8th or 9th grade level.  These vocabulary list are words that students are expected to know by the end of each grade.  I have to admit after reviewing, I did learn a thing or two. 
8th Grade
9th Grade

Emotion Words and Definitions
If you’re looking for the right emotion for your character, but can’t put a finger on it, look no further.  These lists include most emotions with descriptions.
Emotional Vocabulary List
Definition of Emotions

Readability Checkers
Readability checkers determine the reading level of content based on grade or comprehension.  This can be especially useful when writing children’s stories or to ensure books for adults meet the average.
Readability-Score
The Writer

If you have additional resources that can help improve writing, please share.