Color Pencils

My name is Olivia. I love your website and I love to doodle! I have a question for you. My teachers always make us use color pencils and no crayons or markers. I find that the color pencils leave a lot of spaces blank, then we get in trouble because of that or we don't color it because it is fine how it is. How can we convince our teacher to let us use crayons at least? Or how can we use the coloring pencils maybe, differently?