How Handwriting Boosts the Brain is an article in the Wall Street Journal extolling the brain benefits of students and adults writing by hand instead of always using media devices.
TwistyNoodle.Com is a site with coloring sheets, worksheets, and handwriting practice. While not a huge fan of this sort of activity, for the occasional use, they do have some cute primary themes organized by topic.
Kidzone Cursive Writing site has printables with traceable letters for student practice.
Handwriting for Kids has practice letters with the correct sequence of pencil strokes detailed.