When I was a Common Core Coach for our state this summer, almost every group of teachers I worked with wanted to discuss Reading Foundations Skill 3.3.a: Identify and know the meaning of the most common prefixes and derivational suffixes.
A derivational suffix changes the meaning of the word and usually changes the part of speech of the word. For instance, happy is an adjective. If you add the suffix -ly to happy, it becomes happily, an adverb.