Spectrum Math 2015
The 2015 edition of the Spectrum Math series states that it is "Correlated to the Current State Standards." This means that significant changes were made to bring it into alignment with the CCSS (which most states align to). Although the general format and structure of the books remain the same, the topics differ significantly at the middle school levels and reflect more advanced algebra and geometry content as well as increased content in data, probability, and statistics. Each chapter starts with a pretest (Check What You Know) and ends with a posttest (Check What You Learned). Lessons within each chapter cover a progression of skills. Instruction is minimal but examples precede each worksheet. To give you an idea of the differences in this edition, previously the 7th grade book started with chapters on whole numbers, fractions, decimals, percents, and calculating interest but the new edition starts with rational numbers, expressions, equations, and inequalities. Both cover ratios and proportions but terminology and content are different. The previous edition had sections on both English (customary) and metric measurement while those topics are not covered in the 2015 edition. Both editions have sections on probability, statistics, and geometry but the content of each is different and the newer edition is more advanced. There is also a greater emphasis on problem solving and word problems in the newer edition. In general, I would say the 7th grade book is roughly one year ahead of the previous edition. These workbooks are 160 pages in length.
The topic specific workbooks (124 pages each) that are available for the 6th through 8th grade levels have also had changes based on the newer standards. Every chapter still has a pretest and posttest, along with a mid-year test and final test. The Algebra workbook has added chapters on expressions and equations and systems of equations and has removed chapters on probability and graphs and algebra and geometry. Chapters in the Data Analysis/Probability workbook have completely changed to probability models, calculating probability and compound events, statistical thinking, measures of central tendency & measures of variability, displaying data, and scatter plots & bivariate data. The Geometry workbook is basically the same as the previous edition, but all of the angle and triangle concepts have been combined into one chapter, which is