I'm reading Sunni Brown's book The Doodle Revolution, and this is from two of the exercises in chapter four:
Sunni Brown has a six minute TED talk, Doodler's Unite! that includes some of the material from the book. I've drawn cartoon animals on sunny landscapes since I was in high school (thanks to dull history lessons at Copleston High), and I love the idea of drawing, but my practice always falls short. Doodling has a much lower bar.