Line Up the Points: Adding and Subtracting Decimals

Student Task

• Write 4.75 + 1.5 on the board and ask students to predict the answer before showing the column method.
• Teach lining up the points and placeholder zeros, then do the first questions of activity 1 together.
• Students complete the rest of the worksheet; answers are in the answer key.

Classroom Use

• Class shop: price classroom items in dollars and cents; students buy two items and work out the total and change from $10.
• Long jump: measure standing jumps in meters and find the difference between two jumps.
• Estimate first: students round each number, estimate, then calculate and compare.

Differentiation

Support: start with tenths only and use grid paper. Challenge: add three decimals and subtract from whole numbers (10 − 3.48).

Answer Key & Assessment

Activities 1 and 2 check calculations; activities 3 to 5 check estimating and problem solving (answer key included).

Learning Objectives

• Add and subtract decimals to hundredths by lining up the decimal points.
• Use placeholder zeros and estimate answers by rounding.
• Solve money and measurement problems with decimals.

Teacher Tips

Use grid paper so each digit has its own box. Most errors come from lining up the last digits instead of the decimal points.

What's Included

• 6-page printable PDF lesson pack: teacher lesson plan with timings, materials and differentiation
• Key vocabulary list (4 words with meanings and examples)
• Student worksheet (5 activities)
• Editable Word version of the worksheet
• Complete answer key (also as a separate PDF)

Additional Files

• Editable Worksheet (Word) (DOCX)
• Answer Key (PDF) (PDF)

Teacher Reviews