📈 Math Intervention

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💯 Builds 6.NOS.B.3

Decimals & Place Value

Read, compare, round, and compute with decimals — the foundation for money, measurement, and percents.

Learning objective

I can read, compare, and round decimals and add, subtract, multiply, and divide decimals to solve money and measurement problems.

🎯 Builds 6.NOS.B.3 📚 4 lessons ⏱ 30 min

Core question

How can I model, solve, and explain decimals & Place Value so another student understands my thinking?

Concept spine

Understand the situation, represent it, choose the strategy, then prove the answer.

Evidence of mastery

Score 80% or higher, correct one missed item in Smart Review, and write a complete explanation using at least one vocabulary word.

Key vocabulary

  • decimal — A number with a dot showing parts smaller than one.
  • place value — The value a digit has from its position.
  • tenths — The first place right after the decimal point.
  • hundredths — The second place right after the decimal point.
  • round — To make a number simpler but close in value.
  • product — The answer when you multiply two numbers.

Materials

  • Place value chart
  • Base-ten blocks or decimal grids
  • Pencil and grid paper
  • Play money (coins and bills)
Mission

Rebuild decimals & Place Value

Move from model to strategy to independent proof using place value, compare & round, operate, and money.

Success looks like

Show, solve, explain

Students can represent the idea, solve accurately, and justify why the answer makes sense.

Teacher evidence

6.NOS.B.3

Listen for unit language: halves, tenths, hundredths, equal parts, and benchmark values.

Larger concept

Before students chase speed, they build the whole idea. Use this as the opening map for a small group, tutoring block, or independent recovery path.

Concept spine

The big idea: Decimals & Place Value is about choosing a representation, keeping quantities organized, and defending the strategy.

Understand

Name the quantities

Students identify what is known, what is unknown, and which vocabulary from decimals & Place Value matters.

Represent

Build the model

Use area models, number lines, and place-value charts so students see the size of each quantity.

Strategize

Choose the tool

Students connect the model to place value, compare & round, operate, and money and explain why that tool fits.

Prove

Justify and revise

Students use the discourse frame, check for the likely misconception, and revise the written explanation.

Teacher frame

Open with the larger concept before students touch the practice set: What does the situation mean, what model fits it, and how will we know the answer is reasonable?

Essential question

How do mathematicians use place value, compare & round, operate, and money to make sense of real problems and defend an answer?

Launch

Make the gap visible

Students preview place value, compare & round, operate, and money with one low-floor problem, one model, and one vocabulary check.

Model

Connect concrete to symbolic

Use area models, number lines, and place-value charts so students see the size of each quantity.

Explain

Require math talk

Students complete the frame: "These two values are equivalent because I can show them as ___ and ___."

Transfer

Apply in context

Have students prove the same answer using a visual model and an equation.

Model it

Use area models, number lines, and place-value charts so students see the size of each quantity.

Say it

These two values are equivalent because I can show them as ___ and ___.

Extend it

Have students prove the same answer using a visual model and an equation.

Mini-lessons inside the larger topic

Teach the big idea first, then open one mini-lesson at a time. Each mini-lesson has a narrow objective, one teacher move, one model, practice, an error to catch, and evidence to collect.

Lesson 1
Open the concept

Place value

I can explain what place value means before I calculate.

Teacher move
Launch with a low-floor context and ask students to show place value with a model before naming a rule.
Model or example
Compare 0.6 and 0.58. Which is greater? Work it aloud, then cover the steps and ask students to rebuild the reasoning.
Student practice
What is the value of the 7 in 4.73? | How do you read the decimal 0.6? | Which decimal is the largest?
Error to catch
Students may compare digits instead of values, treat denominators as whole-number size, or forget that decimals and fractions can represent the same amount.
Evidence
Annotated model and one accurate independent item.
Lesson 2
Build the next piece

Compare & round

I can use compare & round as one part of solving decimals & Place Value problems.

Teacher move
Use the previous mini-lesson as the anchor, then add compare & round with one worked example and one parallel try-it item.
Model or example
Add 7.45 + 12.8. Work it aloud, then cover the steps and ask students to rebuild the reasoning.
Student practice
Round 3.7 to the nearest whole number. | Which symbol makes this true: 0.3 ___ 0.30 ? | Round 5.48 to the nearest tenth.
Error to catch
Students may treat compare & round as a shortcut instead of connecting it back to the model.
Evidence
Annotated model and one accurate independent item.
Lesson 3
Build the next piece

Operate

I can use operate as one part of solving decimals & Place Value problems.

Teacher move
Use the previous mini-lesson as the anchor, then add operate with one worked example and one parallel try-it item.
Model or example
A car travels 48.6 miles on 6 gallons of gas. Find the miles per gallon. Work it aloud, then cover the steps and ask students to rebuild the reasoning.
Student practice
What is 0.9 - 0.45 ? | What is 7.45 + 12.8 ? | What is 20 - 13.6 ?
Error to catch
Students may treat operate as a shortcut instead of connecting it back to the model.
Evidence
Annotated model and one accurate independent item.
Lesson 4
Connect and transfer

Money

I can use money as one part of solving decimals & Place Value problems.

Teacher move
Use the previous mini-lesson as the anchor, then add money with one worked example and one parallel try-it item.
Model or example
Compare 0.6 and 0.58. Which is greater? Work it aloud, then cover the steps and ask students to rebuild the reasoning.
Student practice
What is 5.6 x 0.4 ? | What is 0.45 x 0.3 ? | What is 9.6 / 0.4 ?
Error to catch
Students may treat money as a shortcut instead of connecting it back to the model.
Evidence
Exit ticket plus revised explanation.

How the pieces connect

Students should not experience these as separate activities. Each mini-lesson adds one piece to the same concept spine: understand, represent, strategize, and prove.

Five-session lesson path

This is the teacher-ready pacing model for intervention blocks, tutoring, pull-out groups, or independent catch-up work.

Session 1

Diagnose and name the gap

Teacher move
Assign the pre-quiz, sort students into groups, and launch one low-floor model.
Student work
Take the pre-quiz, complete the diagnostic, and write one goal for the topic.
Evidence
Pre-quiz score, diagnostic score, student goal.
Session 2

Build the concept

Teacher move
Use area models, number lines, and place-value charts so students see the size of each quantity.
Student work
Annotate the worked examples and complete the concept lab discussion frame.
Evidence
Annotated example, vocabulary sentence, model check.
Session 3

Practice with feedback

Teacher move
Conference with students using Smart Review misses and the Error Clinic protocol.
Student work
Complete Practice, Smart Review, and the fluency drill until one score improves.
Evidence
Practice percent, cleared Smart Review item, fluency count.
Session 4

Apply and transfer

Teacher move
Assign Worksheet B and the performance task; listen for the discourse frame.
Student work
Solve a contextual problem, explain the strategy, and revise the explanation.
Evidence
Performance task, revised explanation, exit ticket.
Session 5

Reassess and reflect

Teacher move
Assign the post-quiz, compare growth, and select the next intervention move.
Student work
Take the post-quiz and complete a reflection on what changed.
Evidence
Post-quiz score, reflection, next-step recommendation.

Placement pathways

Use the pre-quiz and diagnostic score to select the right route without lowering the grade-level expectation.

Pre-quiz or diagnostic below 50%

Intensive reteach

Teacher-led model, manipulatives, read-aloud question support, Worksheet A odd items, then one Smart Review item.

50% to 79% or inconsistent explanations

Guided practice

Concept Lab, worked examples, Practice, Error Clinic, Worksheet A/B mix, and an exit ticket conference.

80%+ with clear explanation

Extension and transfer

Worksheet B challenge, performance task, student-created example, and peer teaching using the discourse frame.

Worked examples

Study these three examples — easy to challenge — then head to Practice.

Example 1Warm-up

Compare 0.6 and 0.58. Which is greater?

  1. Write both with the same number of places: 0.60 and 0.58.
  2. Compare the tenths: 6 tenths versus 5 tenths.
  3. Since 6 is greater than 5, 0.60 is greater.
  4. So 0.6 > 0.58.
Answer: 0.6 is greater
Example 2On level

Add 7.45 + 12.8.

  1. Line up the decimal points and add a zero: 12.80.
  2. Add hundredths: 5 + 0 = 5.
  3. Add tenths: 4 + 8 = 12, write 2 and carry 1.
  4. Add ones: 7 + 2 + 1 = 10, write 0 carry 1; then 1 + 1 = 2.
  5. The sum is 20.25.
Answer: 20.25
Example 3Challenge

A car travels 48.6 miles on 6 gallons of gas. Find the miles per gallon.

  1. Set up the division: 48.6 / 6.
  2. Place the decimal point in the answer straight above its spot.
  3. Divide: 48 / 6 = 8, then bring down the 6 tenths.
  4. 6 tenths / 6 = 1 tenth, giving 8.1.
  5. The car gets 8.1 miles per gallon.
Answer: 8.1 miles per gallon

Where do you start?

Six quick questions. We'll tell you whether to skip ahead or dig in.

Practice with instant feedback

Ten questions, self-checking. Aim for 80%+, then try the game.

Answer Drop

Tap a falling tile — or press number keys 1–4 — to match the problem. Five lives — how high can you climb?

Answer Drop

Click the tile that solves the problem — or use number keys 1–4 — before it hits the bottom.

Error clinic

Use this as a quick conference script after a missed diagnostic, a worksheet error, or a low post-quiz score.

Likely misconception

Students may compare digits instead of values, treat denominators as whole-number size, or forget that decimals and fractions can represent the same amount.

Teacher move

Listen for unit language: halves, tenths, hundredths, equal parts, and benchmark values.

Student self-check

Can I show the problem with a model, name the operation or relationship, and explain why my answer is reasonable?

Two-minute conference

  1. Ask the student to point to the exact step where the answer changed.
  2. Have the student restate the problem using one vocabulary word from this topic.
  3. Rebuild one simpler example together, then ask the student to solve a parallel problem alone.

Performance task

Students apply decimals & Place Value in a short constructed-response task. This gives publishers, teachers, and families evidence beyond multiple choice.

Scenario

Decimals & Place Value in the real world

Create a realistic situation where someone must use place value, compare & round, operate, and money. Solve it two ways: first with a model or diagram, then with numbers or symbols. Finish by explaining why the answer is reasonable.

Student deliverables

  • A labeled model, diagram, table, or number line.
  • A complete solution with units or labels.
  • A written explanation using at least one vocabulary word.
  • A revised answer after checking for the common misconception.

Notebook prompts

  1. Before I solve, the quantities I notice are ___ and ___.
  2. A model that helps me understand decimals & Place Value is ___ because ___.
  3. One mistake a student might make is ___; I would fix it by ___.
  4. My post-quiz goal is ___, and the evidence I will use is ___.
4 · Publishes math thinking Accurate answer, efficient strategy, clear model, complete explanation, and correct vocabulary.
3 · Meets standard Accurate answer and a mostly clear strategy with enough explanation to follow the thinking.
2 · Developing Partially correct work; model or explanation shows a gap that can be repaired with feedback.
1 · Needs reteach Misconception is still present; student needs a concrete model and a smaller parallel problem.

60-second fluency drill

Answer as many as you can before the clock runs out — speed plus accuracy builds automaticity.

Vocabulary flashcards

Tap a card to flip it. Use 🔊 to hear the word and meaning.

decimal
A number with a dot showing parts smaller than one.
place value
The value a digit has from its position.
tenths
The first place right after the decimal point.
hundredths
The second place right after the decimal point.
round
To make a number simpler but close in value.
product
The answer when you multiply two numbers.

Pre-Quiz & Post-Quiz

Assign the pre-quiz before the station and the post-quiz after. Each comes in a student version and a teacher (auto-graded) version.

Quiz links are wired from assets/forms-links.js once the Google Forms are generated (see scripts/intervention/forms.gs).

Track your learning

Check each box when you can do it on your own.

Differentiation

Level 1 — Support

Level 1 (support): use the Materials manipulatives, study the worked examples, and work one step at a time.

Level 2 — Stretch

Level 2 (stretch): finish the ★ challenge on Worksheet B and explain your reasoning in words.

Success criteria

  • I can represent the math with a model, table, number line, diagram, or equation.
  • I can use place value, compare & round, operate, and money accurately and explain why the strategy fits the problem.
  • I can find and correct an error by naming the misconception.
  • I can prove growth with a post-quiz score, an exit ticket, and a written explanation.

Language supports

Pair every symbolic step with a visual phrase such as 'three tenths' or 'five equal parts'.

Talk frame: These two values are equivalent because I can show them as ___ and ___.

Talk-Write-Revise: say the strategy with a partner, write one complete explanation, then revise it with a vocabulary word.