Overview

Grade 1 Math

B1. Number Sense

1. B1.1 Whole Numbers

1.2 Missing values in a number grid up to 100

Missing Values in a Number Grid Up to 100

Learn the row and column patterns that let you fill in any missing number on a hundreds chart without counting one by one.

What You'll Learn

Identify that moving one space right on a number grid adds \(1\) and moving left subtracts \(1\).

Recognize that moving one space down adds \(10\) and moving one space up subtracts \(10\).

Apply a neighboring number to solve a blank, for example \(43+1=44\).

Check every answer by working from the opposite direction, such as \(45-1=44\).

Compare numbers in the same column to see they are always all even or all odd.

Solve full hundreds chart puzzles by combining row and column patterns together.

What You'll Practice

Finding missing numbers in partially filled number grids

Counting forward and backward to fill in grid blanks

Identifying number patterns in horizontal and vertical sequences

Why This Matters

Mastering number grids builds your number sense and mental math skills, which are essential for addition, subtraction, and understanding place value. These skills help you quickly navigate larger numbers and solve problems more efficiently in everyday math.

This Unit Includes

1 Video lesson

Practice exercises

Learning resources

Skills

Number Sense

Counting

Place Value

Number Patterns

Number Grid

ON Curriculum Aligned