http://www.nma.art/courses/the-12-principles-of-animation/

In this course, professional animators Michael Cedeno, Kathleen Quaife-Hodge, and Marshall Lee Toomey will introduce you to the 12 principles of animation. You will explore timing, slo-in slo-out, squash and stretch, arc, anticipation, pose to pose, straight ahead, and many more. Kathleen will show you how to set up a downshooter to transfer your pencil sketches to an actual film. Michael will demonstrate how to employ the principles in animated scenes to achieve good flow and continuity. You will practice developing appealing characters and exaggerating your design to evoke emotions. Lastly, Marshall will walk you through a quick overview of clean-up animation. After this course, you will become familiar with the 12 principles of animation; from there, begin to utilize them in your creation.