Lesson 3: Number Sense

The ninth installment of a 21-part module has pupils compare integers and rational numbers in decimal and fraction form. They match stories to number lines and compare values in the stories.

Develop young mathematicians' ability to compare fractions with investigation into the number 1/2. After brainstorming a list of fractions equivalent to 1/2, children identify a pattern in the numerators and...

Have young mathematicians subtracting fractions in no time with this manipulative-based math instructional activity. Using their sets of fraction circles, learners explore a number of word problems involving the subtraction of fractions...

Use this video to show older elementary mathematicians that they can compare numbers using the same thinking that they did when they were in the first grade. Sal compares decimal numbers using the greater than and less than symbols. He...

Find another way to write a fraction. Using long division, the video shows how to convert a fraction into a decimal. Learners use their knowledge of fractions to then set up the division problem. 

Using a number line can provide students with a concrete representation of the value various numbers hold. Sal plots six different numbers on a number line. He includes whole, decimal, and negative numbers.

Sal compares two fractions containing uncommon denominators. He analyzes both fractions using prime factorization. Note: This video may be confusing for learners who struggle or are new to the concept. It would be best used for...

Sal adds a few more steps to these problems as he solves algebraic equations with two steps, though he states that "there's more than one way to do it." Those who become confused by increasingly complicated algebra problems on a test...

In this video, Sal determines if 30/45 and 54/81 are equivalent fractions. He explains that he looks at each numerator and denominator as two numbers multiplied together. Then he simplifies both fractions to conclude that 30/45 and 54/81...

Compare 2 numbers to thousandths based on meanings of the digits in each place. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.