I use Openstax Biology 2e as a textbook for my AP Bio and dual credit class. Students can download this text for free, view it on their devices and print it out. You can even purchase a bound copy from Amazon for around $60, which is very reasonable for a textbook.
This is the book I use with my AP Biology / SLU Dual Credit Course.
I have the .pdf file from Openstax broken down into chapters, which I share with my class over google classroom. Students really resist having to carry heavy textbook around (I can’t blame them) and have expressed that they like the digital version. Some even request that I print the chapters for them (which I do.)
As with other textbooks I have used in the past, students do not read chapters unless you give them some kind of assignment that goes with it. Openstax does have chapter questions available, but I prefer to use reading guides which ask students to read the chapter, pausing to answer questions as they go. I have developed reading guides for several chapters and will add more as I go. I often only award a small number of points for reading guides, about 5 pts and mainly look for completion. Reading guides are combinations of fill-in-the-blank, multiple choice, and labeling.
Chapter 1: The Study of Life
Reading Guide 1.1 (doc); pdf
Reading Guide 1.2 (doc); pdf
Answer Key (TpT)
Chapter 2: The Chemical Foundation of Life
Reading Guide 2.1 (doc); pdf | Answer Key (TpT)
Reading Guide 2.2 (doc); pdf | Answer Key (TpT)
Reading Guide 2.3 (doc); pdf | Answer Key (TpT)
Chapter 3: Biological Macromolecules
Reading Guide 3.1-3.5 (doc); pdf | Answer Key (TpT)
Chapter 4: The Cell
Reading Guide 4.1-4.3 (doc); pdf | Answer Key (TpT)
Reading Guide 4.4-4.6 (doc); pdf | Answer Key (TpT)
Chapter 5: Plasma Membrane
Reading Guide: 5-1 – 5.4 (doc); pdf | Answer Key (TpT)
Chapter 6: Metabolism
Reading Guide: Ch 6 (doc); pdf | Answer Key (TpT)
Ch 10 – Cell Reproduction
Reading Guide: Ch 10 (doc); pdf | Answer Key (TpT)
Ch 11: Meiosis
Reading Guide: Ch 11 (doc); pdf | Answer Key (TpT)
Ch 13 – Modern Understandings
Reading Guide: Ch 13; pdf | Answer Key (TpT)
Chapter 14: DNA Structure
Reading Guide: Ch 14 (doc); pdf | Answer Key (TpT)