Additive Thinking and Regrouping · Operations

Mental Math Strategies

Using compensation and decomposition to solve problems without paper and pencil.

Key Questions

  1. 1How does breaking a number into its expanded form make it easier to add mentally?
  2. 2Why might adding 99 be easier if we think of it as adding 100 and subtracting 1?
  3. 3When is mental estimation better than finding an exact calculation?

CBSE Learning Outcomes

CBSE: Mental Arithmetic - Class 3
Class: Class 3
Subject: Mathematics
Unit: Additive Thinking and Regrouping
Period: Operations

Suggested Methodologies

Ready to teach this topic?

Generate a complete, classroom-ready active learning mission in seconds.

Generate a Custom MissionBrowse Lesson Plan Templates

More in Additive Thinking and Regrouping

The Logic of Regrouping

Developing a conceptual understanding of carrying over and borrowing by bundling units.

2 methodologies

Inverse Relationships

Exploring how addition and subtraction undo each other to check for accuracy.

1 methodologies

Browse curriculum by country

AmericasUSCAMXCLCOBR
EuropeUKIEFRDEESITNLPTSE
Asia & PacificINSGAU