Still Life with Mushrooms

Here's an exercise practice from my pastel workbook. I'm still not working with the type of paper and utensils that the book talks about, but I'm improvising. For pastel paper, I'm using colored construction paper, and I have some charcoal pastels and some oils, not quite in the colors suggested. Not sure I understand light and dark yet, but I get the idea, you should shade in your darker areas first, then layer in the lighter areas. Still needs work.