Math lesson plan · 4th grade (Year 5 in England) · 45 minutes
Add tenths and hundredths written as fractions
Decimals and percentages
CCSS 4.NF.C.5England: Y4 Fractions (including decimals)
Objective and success criteria
Students will: Add tenths and hundredths written as fractions.
- I can answer questions on today's skill on my own, without help.
- I can explain each step and say why it works.
- I can check my answer and spot a mistake.
Before and after
Needs first: Tenths and hundredths as fractions
Leads to: the next skill in this area.
Materials: Place value chart with tenths and hundredths, Hundred squares, Number lines, Mini whiteboards and pens, Printed student sheet (below).
Warm-up · 5 min
- Quick retrieval from earlier learning (Tenths and hundredths as fractions). Students answer on mini whiteboards.
- Show answers together and note who needs support in the main task.
- 4/10 + 98/100 = __/100 → 138Prompt: Change 4/10 into hundredths first.
- 10/100 = __/10 → 1Prompt: Divide top and bottom by 10.
- 6/10 + 69/100 = __/100 → 129Prompt: Change 6/10 into hundredths first.
Hook · 5 min
- Show two prices or race times with decimals and ask which is bigger, then why.
- Share the objective: Add tenths and hundredths written as fractions. Read the success criteria together.
I do: model it · 10 min
- Work through the example out loud, saying why you do each step, not just what you do.
- Example: 4/10 + 1/100 = ?/100
- Step 1: 4/10 = 40/100
- Step 2: 40 + 1 = 41
- Step 3: 41
- Answer: 41
- Pause after each step and ask a student to say what comes next.
We do: guided practice · 10 min
- Do these together. Students try each step on whiteboards before you reveal it.
- Use the hints as prompts rather than giving the answer.
- 6/10 + 18/100 = ?/100 → 78Prompt: Change 6/10 into hundredths.
- 3/10 + 12/100 = ? Write the answer as a decimal. → 0.42Prompt: Write both as hundredths first.
You do: independent practice · 10 min
- Students work on the student sheet. Circulate and check the first two answers of every student early.
- Students who finish: write a question of their own for a partner, with the answer.
The 8 questions are on the student sheet below, with answers in the key.
Exit ticket · 5 min
- Two questions on their own. Sort answers into got it / nearly / not yet to plan the next lesson.
- 7/10 + 29/100 = ?/100 → 99Prompt: Change 7/10 into hundredths.
- Sam filled 4/10 of a jar with red beads and 20/100 with blue beads. What fraction of the jar is full? Give it in hundredths. → 60/100Prompt: Tenths and hundredths need the same denominator before adding.
Watch out for
- Thinking 0.45 is bigger than 0.5 because 45 is bigger than 5.
- Moving the digits the wrong way when multiplying or dividing by 10.
Support and stretch
Support
- Review first: Tenths and hundredths as fractions.
- Use concrete materials: place value chart with tenths and hundredths.
- Give the first step of each question, or a partly worked example to finish.
- Pair with a confident partner for the guided practice.
Stretch
- Explain a common mistake in writing and how to fix it.
- Write a word problem that uses today's skill, then solve a partner's.
Homework and more practice
Free online practice with hints and printable worksheets for this skill: eurekami.com/math/grade-4.
Free lesson plan from eurekami.com/lesson-plan-builder