Decimals are one of the most confusing concepts to learners. Unfortunately, many textbooks and lessons tend to move too quickly into the operations with decimals without fully explaining what a decimal point is. This can leave already struggling students feeling hopeless.

This lesson will help you introduce (or re-introduce) decimal points to your class in an engaging way. It uses money to help teach students about decimal points in a way they can understand; and in a way they can become comfortable with the concept of decimal points (separating whole numbers from parts), as well as decimal place values and fractions.

The common core standards addressed in this lesson are as follows:
CCSS.MATH.CONTENT.3.NF.A.1
Understand a fraction 1/b as the quantity formed by 1 part when a whole is partitioned into b equal parts; understand a fraction a/b as the quantity formed by a parts of size 1/b.

CCSS.MATH.CONTENT.4.NF.C.6
Use decimal notation for fractions with denominators 10 or 100. For example, rewrite 0.62 as 62/100; describe a length as 0.62 meters; locate 0.62 on a number line diagram.

CCSS.MATH.CONTENT.5.NBT.A.3.A
Read and write decimals to thousandths using base-ten numerals, number names, and expanded form, e.g., 347.392 = 3 × 100 + 4 × 10 + 7 × 1 + 3 × (1/10) + 9 × (1/100) + 2 × (1/1000).

Math vocabulary review: whole number, numerator, denominator, decimal point, place value, cents.