Textbook? What Textbook?
Most middle school and early high school students either cannot or are not taking advantage of their textbooks as a helpful resource. This does them a great disservice and is particularly common with science textbooks. Talk to your student about reading for comprehension rather than reading to get the reading finished. You may even want to read through part of a chapter together, discussing the material as you go. Also, be sure you spend time reviewing the diagrams and pictures with them so they begin to understand that those are useful as well.