Illustrative Mathematics Grade 2, Unit 9: Putting It All Together
In this unit, your child reviews and stretches the big ideas of 2nd grade. They solve one- and two-step story problems, revisit place value with hundreds, tens, and ones, measure objects with the right tool, and describe shapes by their features. It is a chance to make the year's work feel solid before 3rd grade.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
What is my child learning in Unit 9?
- Solving mixed one- and two-step story problems within 100 and explaining the plan for each step. Learn more: One- and two-step story problems within 100
- Revisiting hundreds, tens, and ones, such as seeing 706 as 7 hundreds, 0 tens, and 6 ones. Learn more: Hundreds, tens, and ones in numbers like 706
- Choosing a ruler, yardstick, or measuring tape for a job and measuring accurately from zero. Learn more: Measuring with a ruler, yardstick, or tape
- Describing and drawing shapes by their number of sides, angles, and faces. Learn more: Naming triangles, hexagons, cubes, and more
Sample questions to try together
These are real questions from our practice. Tap the speaker to hear one read aloud, or the light bulb for a hint, and talk about the answer together.
Question 1 of 3
What is 80 minus 20?
- 50
- 60
- 70
How you can help
- Make up two-step stories during a trip to the store, and ask your child to explain both steps before solving.
- Measure something new each day, like a pillow, a cup, or a window, and let your child choose the tool.
- Ask your child to describe a shape without naming it, such as "four sides and four square corners," while you guess, then switch.
Where kids can get stuck
- Giving the in-between amount as the answer to a two-step problem.
- Reading the 4 in 482 as four, not four hundred.
- Losing count of angles by starting at one corner and stopping at a different one.
Practice makes perfect
Bobby's Math Club has practice problems that adapt to your child’s level, each with a detailed explanation and an easy-to-follow video, so your child can build confidence in these skills one step at a time.
Words your child will hear
- two-step problem
- A story problem that needs two math steps to solve.
- hundreds
- Groups of 100. In 706, the 7 means 7 hundreds, or 700.
- place value
- The value a digit has because of its spot in a number: ones, tens, or hundreds.
- ruler
- A straight tool marked in inches or centimeters for measuring length.
- measuring tape
- A long, bendable strip marked with units, for measuring big or curved things.
- angle
- The corner where two sides of a shape meet.
- quadrilateral
- Any flat shape with 4 straight sides and 4 angles.
- hexagon
- A flat shape with 6 straight sides and 6 angles.
Ready to build your child’s confidence with 2nd grade math?
In Bobby's Math Club, your child practices these skills at just the right level, with a hint when they need one, a clear explanation after every question, and kid-friendly videos. Unlimited practice is free.
Join the club
Written by Robert “Bobby” Barnett
Bobby is an award-winning math teacher, the author of Meet Every Learner’s Needs, and the father of two elementary-school math learners. He uses Bobby’s Math Club with his own kids a few times every week. Learn more or contact Bobby.
Which math standards does Illustrative Mathematics Grade 2 Unit 9 cover?
Illustrative Mathematics Grade 2 Unit 9 covers these math standards. Each one links to what it means, sample questions, and teaching strategies.
- 2.OA.A.1: Use addition and subtraction within 100 to solve word problems.
- 2.NBT.A.1: Understand that the three digits of a three-digit number represent amounts of hundreds, tens, and ones.
- 2.MD.A.1: Measure the length of an object by selecting and using appropriate tools.
- 2.G.A.1: Recognize and draw shapes having specified attributes.
For teachers: Unit names and order vary between editions and districts, so your school’s own materials have the exact sequence. Learn how Bobby's Math Club can help your students grow.