Math Mammoth Grade 1-B Worktext is the student book for the latter half of grade 1 mathematics studies. It covers addition and subtraction facts, telling time to the half hour, measuring, adding and subtracting two-digit numbers, and counting coins. The "worktext" means it contains both the instruction ("text") and the exercises for the student ("work"). This curriculum is aligned to the Common Core Standards. This is the full-color version; in other words, the inside pages are in full color. Please note this book does not contain an answer key.