I definitely would take another class. I think next time it would be fun to do an acrylic or oil paint class (even if it would be REALLY expensive to buy more paint and brushes and whatnot).
See pictures below (sorry the pictures aren't the best!)
In the last class, we did a water picture with both still and moving water and using all colors (I have to give credit to our instructor on the birds - I had such a hard time with those!)