Bridges in Mathematics Grade 2, Unit 6: 3D Shapes & Numbers to One Thousand
In this unit, your child adds and subtracts with three-digit numbers, working by hundreds, tens, and ones, and adds or takes away 10 or 100 in their head. Alongside the numbers, they look at solid shapes such as cubes, counting faces (flat sides), and name flat shapes by their sides and angles. It builds on place value to 1,000 and leads into measuring, money, and time.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
What is my child learning in Unit 6?
- Adding and subtracting within 1,000 with models and drawings, then connecting them to a written method with regrouping. Learn more about adding within 1,000: Adding within 1,000 · Learn more about subtracting within 1,000
- Finding 10 more, 10 less, 100 more, or 100 less than a number like 432 in their head, by changing one digit. Learn more: Adding or taking away 10 or 100 mentally
- Naming triangles, quadrilaterals, pentagons, hexagons, and cubes, and describing them by their 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
A toy store had 450 toy cars and sold 120 of them. How many toy cars are left?
- 320
- 570
- 330
How you can help
- Look for solid shapes around the house, like a cereal box, a number cube, and a can, and count the faces on each one together.
- Pick a number from a page or a sign, like 452, and ask for 10 more, 10 less, 100 more, and 100 less. Ask which digit changed each time.
- Add two three-digit prices from a menu or flyer and let your child talk you through the hundreds, tens, and ones, regrouping when a place goes past 9.
Where kids can get stuck
- Changing the wrong digit, saying 100 more than 432 is 442.
- Writing each column's total straight down, so 365 + 248 becomes 51013 instead of 613.
- Naming only perfect-looking shapes, refusing to call an uneven six-sided shape a hexagon.
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
- hundreds
- Groups of 100. In 706, the 7 means 7 hundreds, or 700.
- regroup
- Trading 10 ones for 1 ten, or 1 ten for 10 ones, to add or subtract.
- mentally
- In your head, without writing it down or using objects.
- face
- A flat side of a solid shape. A cube has 6 faces.
- cube
- A solid shape with 6 square faces that are all the same size.
- 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 hundreds, tens, and ones?
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 Bridges in Mathematics Grade 2 Unit 6 cover?
Bridges in Mathematics Grade 2 Unit 6 covers these math standards. Each one links to what it means, sample questions, and teaching strategies.
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.