Unit 2: Decimals (Grades 4-6th)

Decimals contain a point that indicates which part of the number is a whole number, and which is the fraction. Decimals are used everywhere you look! You’ll find decimals where money is involved, because it’s a lot easier to handle numbers than if we used fractions. You’ll also find engineers, scientists, teachers, moms, and doctors using decimals in their everyday life! We’re going to learn how to add, subtract, multiply, divide and use decimals in the real world.

If your student has had some amount of work in decimals, use the practice tests at the back of each of the decimals workbooks to determine the appropriate level for your student.

Please note: a beginner simply means that the math concept being introduced is new to the student. An intermediate  student has seen the concept, but needs more work with it to fully understand it, and advanced students are ready for the practical application of the concept. Please note that students may switch between beginner, intermediate and advanced at any time (something even within a single day). These terms describe a student’s interest and ability, not grade or age.

Use this program to support your educational goals for your student and enjoy the learning adventure!

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Decimals Session #1

Intro to Decimals & Place Value

Uses Decimals Workbook #1

Decimals are used to write a number than is not a whole, like two-and-a-half. Decimals are numbers that are between whole numbers, for example: less than 9 but greater than 8. We're going to introduce how to build a decimal number using place value (100, 10, 0.1 and 0.01), run a Candy Shop and a Fast Food Restaurant, learn how to measure length in the metric system, introduce geography and mapping, track sea turtles and the speed our magnetic North Pole wanders over the centuries!

Skills: Introducing decimals, building decimals to represent real-world problems, measuring in Metric System, place value for ones, tens, and hundreds.

Decimals Session #2

Converting Decimals & Fractions

Uses Decimals Workbook #1 & #2

We’re going to expand on decimals by learning about money, writing numbers to the hundredths and thousandths, and relating decimals back to fractions. We'll have fun with math on the Farm by running fences, handling money, measure for new pens, scheduling horse lessons and more. We'll also explore supernova explosions and calculate speeds in the universe, track migrations of butterflies and arctic birds, and scale mamma polar bears with her cubs.

Skills: Expanded notion to the hundredths and thousandths, writing decimals as equivalent fractions, and measuring in the Metric System, making decisions based on data and identifying patterns using decimals.

Decimals Session #3

Adding & Subtracting Decimals

Uses Decimals Workbook #2

We're going to continue our adventure by learning about decimals, learn how to use decimals to run a family grocery store, go on a scavenger hunt at the library, discover how to do decimal rounding with big numbers as well as money calculations, explore explosions on the sun and make your own decimal wheel! 

Skills: using zero as a placeholder, adding and subtracting decimals, rounding decimals to tenths and hundredths, introducing multiplying decimal numbers, tallying money totals and counting back change, converting time to decimal notation, estimating speeds and scales from photograph information, and continuing to work with decimals in our word problems.

Decimals Session #4

Multiplying Decimals

Uses Decimals Workbook #2 & #3

We dive deeper in decimal multiplication and learn how to ballpark our answers so we really understand how large (or small) our final answer should be. Let's learn how to take over a family business and make sure we're turning a profit, get lost in a math maze, and build a decimal dodecahedron! We'll focus on money and accounting calculations and continue to explore the Metric System. Advanced students will explore craters on moons and other planets and estimate stellar magnitudes. 

Skills: Decimal multiplication, dividing a decimal by a whole number, using zero as a placeholder, different ways to express remainders, how to handle remainders as decimal fractions, and rewriting decimal problems so they are fun and easy to do. 

Decimals Session #5

Dividing Decimals (Part 1)

Uses Decimals Workbook #3

This session starts our journey into dividing decimals. You'll get to go on a Decimal Scavenger Hunt, play decimal board games, practice with your Powers of Ten, and finish up the previous math projects from the first four sessions (Running a Farm, Fast Food Restaurant, Grocery Store, and Donut Shop). The more you practice your decimal division, the better your skill level will be!

Advanced students will get to sit in on a college-level chemistry class and learn how we use decimals with chemical reactions and calculating molecular concentrations. 

Skills: multiplying decimals, dividing by decimal numbers, powers of ten, word problems, significant figures (sig figs) and making sure students really understand all four operations: addition, subtraction, multiplication and division of decimals, and different types of parentheses like brackets and braces.

Decimals Session #6

Dividing Decimals (Part 2)

Uses Decimals Workbook #4

This session expands on division by learning how to divide by decimal numbers. You'll learn how to build number patterns and solve word problems, get lost in a decimal mystery using logic, spin around in a decimal maze, roll your way through a decimal dice game and more! You'll get to practice all four decimal operations as you work through the activities in your Earth Club project.

Advanced students will get to work through the type of math that electrical and electronic engineers use in their circuit design in addition to working through the Earth Club math project.

Skills: number patterns, decimal division (dividing decimal numbers by both whole numbers and decimal numbers), word problems, all four operations (adding, subtracting, multiplying and dividing) decimals with practical applications including accounting, rounding, unit pricing, estimating,  graphing and averaging.

Decimals Session #7

Four Operations with Decimals

Uses Decimals Workbook #4

This session is packed with fun projects, including setting up a super fun Family Math night for your whole family, learning how to run a Fundraising project (and well able to tell how profitable you are), take a side-trip into the world of prime numbers, and weave our way through a Rational Number maze! 

Since this is our final session in decimals, also review all four operations: addition, subtraction, multiplication and division, and focus on practical application of how we use decimals in everyday life. We'll review both decimals and fractions before we move onto our next block.

Advanced students will get to work through the type of math that astronomers get to use when they are making their scientific discoveries!

Skills: all basic operations with decimals and fraction equivalents, accounting skills, estimating, rounding, fraction-decimal equivalents, rational numbers, prime numbers, and using math as a tool to solve real-world science and engineering problems.

Math Quick Checks

These Math Quick Checks are Common Core aligned. They are exactly what you need to quickly check for understanding or assess student learning. They can be used as assessments, homework, or to help reteach a skill in case your student has gaps.

Decimals Review

Finished with decimals? Watch the video below for a full-course review session and take notes as you go along.

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