Measuring Length
Units, Tools, and Estimates
About this book
Take away, compare, then check.
Six short modules take learners from crossing out counters to choosing a model for story problems and checking answers with addition. Every module follows the same seven LessonCrest steps, with help that fades as confidence grows.
- Take away and say what is left
- Count back on a number path
- Compare two groups to find the difference
- Use addition facts and go back through ten
- Story problems, review pages and an exit check
- Answers that explain why, with help for common mistakes
Look inside
What this book covers
Covered
What this book covers: taking away, counting back, comparing two groups, finding a missing part, subtracting through ten and story problems, with counters, ten-frames, number paths, bar models and equations.
Not covered
Not covered here: two-digit subtracting and regrouping (they come after place value).
Before you start, you should be able to
- Count up to 20 objects.
- Show a number on a ten-frame.
- Know that a whole is made of parts.
Things to have
Use real objects and read directions aloud whenever needed.
Notice
Pictures in this book are simplified learning models. Check answers with the explanations at the back of the book.
The steps in this book
- Step 1: Get Ready
Check the skills you need before you begin. If something feels tricky, an adult can help you start in the right place.
- Step 2: Learn It
Read a short, clear explanation of the new idea and the words that go with it.
- Step 3: See It
Watch the idea being used, one step at a time, in a worked example.
- Step 4: Try It Together
Practice with prompts and help cues. The help gets smaller as you get stronger.
- Step 5: On Your Own
Practice on your own with different kinds of questions, and explain your thinking.
- Step 6: Look Back
Look back at earlier learning so it stays strong, then check where to go next.
- Step 7: Check and Fix
Check your answers. Each answer explains why, names a common mistake, and shows how to fix it.
What is in the book
The modules
- Module 1: Take away and say what is leftPages 5–14
- Module 2: Count back on a number pathPages 15–24
- Module 3: Compare to find the differencePages 25–34
- Module 4: Think addition to subtractPages 35–44
- Module 5: Subtract through tenPages 45–54
- Module 6: Choose a model and checkPages 55–64
Contents
- Readiness check, pp. 3–4. Before Module 1. Its table tells you where to start.
- Modules, pp. 5–64
- Checkpoints, pp. 14, 24, 34, 44, 54, 64. The last page of each module.
- Mixed review, pp. 65–68. Questions from across the book, mixed together.
- Exit check, pp. 69–70. A last check across the book.
- Reflect and repair, p. 71
- Try again, p. 72. Fresh questions like those in the exit check.
- Further practice, pp. 73–75. More pages of step 5, On Your Own.
- Extra practice, pp. 76–84
- Answers and explanations, pp. 85–100. Notes in this part are headed “Why”, “Common mistake”, “Help” and “Look for”.