A fun tighten up activity is painting with water onto newsprint.
Practice making brush strokes like the big brushes of decorative
painting. Spirals starting from the center using the tip of the
brush, crescents, comma strokes, or take it to Asian art with Chinese
brush strokes like bone stroke, airplane stroke, etc.
It takes a lot of concentration, but can be repeated over and over
with the water. As soon as it dries you can do more. No one has to
see your mistakes. I had my 10th graders doing this. After the
laughter ended they had a new appreciation. Then they can try double
loading their brushes to make blended and graduated values in one
stroke. Try Donna Dewberry's "One Stroke" if you've never done this
before. Her video is cheap at Walmart.