Phonics includes the relationship between letter(s) and the sounds they make. Phonemic awareness is the ability to hear the sounds that make up a word and does not include letters. There's more to the phonics vs. phonemic awareness question, but that's the simple answer.
When it comes to learning to read and write, students need phonemic awareness. They actually need phonological awareness. Phonemic awareness is a piece of phonological awareness.
You can read more about phonological awareness here.
Phonemic Awareness
So let's begin by building an understanding of phonemic awareness. A phoneme is the smallest unit of sound. For example, /m/. So the word cat has three phonemes–/c/ /a/ /t/. The word ship also has three phonemes–/sh/ /i/ /p/. Yes, it has four letters, but that doesn't matter. Remember phonemic awareness is the ability to hear sounds in a word and has nothing to do with the letters (eventually it will, but that's phonics).
There are eight skills related to phonemic awareness. Studies have shown that a student's ability to segment and blend are predictors of reading readiness.
Phonics
Phonics is a means for teaching students how to read and spell using letters or groups of letters. Most kindergartners start the school year learning letter names and sounds. With that knowledge, they eventually read words by blending the sounds together.
Generally, student are instructed with a sequence of phonics skills.
You can read more in depth about phonics and the alphabetic principle here.
Phonics versus Phonemic Awareness
So to wrap it up, phonics and phonemic awareness are two different things. However, phonics will eventually depend on a students phonemic awareness so it's an important piece of literacy that must be developed.
If you're looking for an activity, orthographic mapping is a great way to combine phonemic awareness and phonics. Get it in The Nook.