This Answer Key accompanies the HIS Story of the 20th Century Middle School Workbook (sold-separately) and includes answers to the questions, worksheets, and books reviews. Both the workbook and the answer key accompany the textbook, HIS Story of the 20th Century. You can purchase HIS Story of the 20th Century and HIS Story of the 20th Century High School Workbook on Amazon, PayHip, or Currclick. Together, they create a one-credit high school history course. I hope this will be a blessing to parents and teachers using HIS Story of the 20th Century textbook and workbook.