In a nutshell
ENSSA uses number line estimation as a measure of children’s understanding of numerical magnitude. Number line estimation tasks ask children to estimate where a number belongs on a bounded number line.
The skill being developed is broader than completing the task itself. Magnitude estimation reflects children’s developing mental representation of number size, often described as a mental number line. Children build this representation through many experiences connecting number names, numerals, quantities, order, position, and distance.
Linear representations are especially important because they make magnitude visible. Larger numbers should look, feel, or extend physically further than smaller numbers. For example, a train of 9 connecting cubes is longer than a train of 5; 18 is further along a number path than 12; and 70 is closer to 100 than to 0 on a bounded number line.
In bounded number line tasks, students are shown a line with labelled start and end points and asked to place a number in the correct approximate location. In Foundation, number lines typically range from 0–20, while in Year 1 they extend to 0–100.
Early number line estimation may initially be attempted as incrementing: counting up the line until the target number is reached without considering the number in relation to the endpoints. For example, if the line finishes at 20, then 9 must be before halfway. As students develop, they increasingly use numerical magnitude, relative size, place value, benchmark numbers, halfway points, and distance to estimate locations more efficiently.
Instruction should build children’s understanding of linear number magnitude through repeated opportunities to build, compare, locate, move along, and explain quantities using linear representations such as connecting-cube trains, rows of counters, bead strings, number tracks, number paths, marked number lines, open number lines, and bounded number lines.
This guidance is designed for classes where ENSSA results indicate a class-wide need to strengthen number line estimation or broader magnitude estimation.
See also: Magnitude Comparison and Number Sequence
Teaching guidance
06Resources for all teachers (Tier 1)View 3 resourcesHide 3 resources↓
For schools and teachers using Ochre curriculum materials
Choose the curriculum used by your school, then find the relevant Foundation or Year 1 resource.
Make sure you’re logged into Ochre first, then open the resource link.
This section is for teachers using Ochre units as part of Tier 1 mathematics instruction in Victorian Curriculum settings, including MACS and CESL schools.
Use Ochre unit lessons when students need teaching or reteaching. Use Ochre Daily Review when students have already been taught the skill and need practice, reactivation or fluency-building.
Step 1: Where does this sit in your teaching sequence?
The skill has not yet been taught and is coming up soon
Let the scheduled Ochre lesson address it. Consider brief pre-teaching for students flagged by ENSSA.
The skill has not yet been taught and is scheduled much later this year
Consider bringing the relevant lesson section forward for flagged students only — check prerequisite lessons first.
The skill has already been taught
Go to Step 2 below.
The skill was taught a while ago, last term or last year
Start with Daily Review as a quick reactivation and accuracy check. If students are still inaccurate, go to Step 2.
Step 2: How are students performing right now?
Use this once you’ve confirmed the skill has already been taught.
Students are inaccurate or unsure
Use the Ochre unit lesson section first — not Daily Review.
Most students are inaccurate
Reteach the relevant modelling/guided-practice section to the whole class.
A few students are inaccurate but most are secure
Use the lesson section for small-group reteaching with flagged students only.
Students are accurate but slow or inconsistent
Use Daily Review — do not run a full reteach.
Has this skill been introduced?
This only asks about timing. Whether the class is accurate is something Daily Review over the next few days will show; it does not need to be judged in advance.
Yes
Use the Daily Review resource below, every day, for an initial five consecutive instructional days, regardless of how accurate the class is assumed to be.
No, but it is coming soon
Do not start Daily Review yet. Read the background sections (Teaching guidance; Vocabulary, representations and stem sentences) and preview the unit lesson below now, ahead of when it is scheduled.
No, and it is not scheduled soon
Check curriculum sequencing and prerequisite knowledge. Consider brief, targeted pre-teaching for the students ENSSA flagged, not a full classwide response ahead of schedule.
After five days of Daily Review
One brief daily note is enough: accuracy, independence and efficiency, not a per-student written record.
Clear improvement, not yet secure
Continue the same Daily Review resource.
Most accurate and increasingly efficient
Continue Daily Review as ongoing cumulative practice; no full reteach is needed.
Most students remain inaccurate or dependent on support
Use the unit lesson section to teach it explicitly, not Daily Review.
Most students are secure, but the same smaller group persists
Keep whole-class Daily Review; use the unit lesson materials with that group specifically.
Foundation
Build foundations for this skill.
FN03V Counting and place value 2Use this when Foundation students need work on ordered position before moving to less-supported number-line tasks.
FN03V Counting and place value 2
Builds prerequisites for magnitude estimation: number tracks to 20, missing numbers, one more/one less, and ordering positions.
Number tracks, missing numbers, one more/one less and ordering.
FN06V Counting and place value 3, Lesson 1Use this when students need additional practice with position language such as first, last, before, after and between.
FN06V Counting and place value 3, Lesson 1
Supports ordinal position on a number track — a useful precursor to number-line estimation.
This is prerequisite work. It does not directly teach bounded number-line estimation.
Number–Place Value Daily Review deckUse this when students have already been taught the relevant number-position skill and need reactivation or practice.
Daily Review Topic Deck: Number – Place Value
Practice with ordered position, number tracks, hundred charts, two-digit representations, one more/one less and comparison.
Year 1
Extend this skill through Year 1.
1N01V Counting and place value 1, Lessons 12–13Use this when Year 1 students need teaching or reteaching with number location, ordered position, benchmarks, 100-chart patterns or number-line placement.
1N01V Counting and place value 1, Lessons 12–13. Note: this unit may currently appear under a Year 2 filename — check the unit content and look for 1N01V.
This is the primary Year 1 Ochre resource for number position and location. Teaches locating numbers on a 100 chart and locating numbers to 100 on a number line.
Lessons 12–13.
- If students do not understand number order or location → use this card.
- If students understand order but need practice → use the Number–Place Value Daily Review deck.
- If students are working on movement or distance for addition/subtraction → use 1N06V Lessons 1–3 instead.
1N03V Counting and place value 2Use this when students need reinforcement of two-digit number structure before or alongside number-line location work.
1N03V Counting and place value 2
Provides secondary support for magnitude estimation through two-digit numbers, one more/one less, and place-value representations.
Supports number magnitude but does not replace 1N01V Lessons 12–13 for number-line/location teaching.
1N06V Addition and subtraction 3, Lessons 1–3Use this only when the specific goal is number-line movement for addition/subtraction strategy — not for magnitude estimation itself.
1N06V Addition and subtraction 3, Lessons 1–3
Supports movement and distance on a number line within 20, such as counting on, counting back, or finding the distance between numbers.
The goal is magnitude estimation or locating numbers by order, position and benchmarks — use 1N01V Lessons 12–13 instead.
Number–Place Value Daily Review deckUse this when students have already been taught the relevant number-position skill and need reactivation or practice.
Daily Review Topic Deck: Number – Place Value
Practice with ordered position, number tracks, hundred charts, two-digit representations, one more/one less and comparison.
This section is for teachers using Ochre units as part of Tier 1 mathematics instruction in WA Curriculum v9.0 settings. WA Curriculum calls Foundation year “Pre-Primary.”
Ochre does not yet publish a separate WA-specific resource library. WA unit codes (PPN01W, 1N02W, and so on) map directly to the equivalent Australian Curriculum unit, so the buttons on these cards open the same Foundation and Year 1 Ochre pages as the Australian Curriculum tab.
Use Ochre unit lessons when students need teaching or reteaching. Use Ochre Daily Review when students have already been taught the skill and need practice, reactivation or fluency-building.
Step 1: Where does this sit in your teaching sequence?
The skill has not yet been taught and is coming up soon
Let the scheduled Ochre lesson address it. Consider brief pre-teaching for students flagged by ENSSA.
The skill has not yet been taught and is scheduled much later this year
Consider bringing the relevant lesson section forward for flagged students only — check prerequisite lessons first.
The skill has already been taught
Go to Step 2 below.
The skill was taught a while ago, last term or last year
Start with Daily Review as a quick reactivation and accuracy check. If students are still inaccurate, go to Step 2.
Step 2: How are students performing right now?
Use this once you’ve confirmed the skill has already been taught.
Students are inaccurate or unsure
Use the Ochre unit lesson section first — not Daily Review.
Most students are inaccurate
Reteach the relevant modelling/guided-practice section to the whole class.
A few students are inaccurate but most are secure
Use the lesson section for small-group reteaching with flagged students only.
Students are accurate but slow or inconsistent
Use Daily Review — do not run a full reteach.
Has this skill been introduced?
This only asks about timing. Whether the class is accurate is something Daily Review over the next few days will show; it does not need to be judged in advance.
Yes
Use the Daily Review resource below, every day, for an initial five consecutive instructional days, regardless of how accurate the class is assumed to be.
No, but it is coming soon
Do not start Daily Review yet. Read the background sections (Teaching guidance; Vocabulary, representations and stem sentences) and preview the unit lesson below now, ahead of when it is scheduled.
No, and it is not scheduled soon
Check curriculum sequencing and prerequisite knowledge. Consider brief, targeted pre-teaching for the students ENSSA flagged, not a full classwide response ahead of schedule.
After five days of Daily Review
One brief daily note is enough: accuracy, independence and efficiency, not a per-student written record.
Clear improvement, not yet secure
Continue the same Daily Review resource.
Most accurate and increasingly efficient
Continue Daily Review as ongoing cumulative practice; no full reteach is needed.
Most students remain inaccurate or dependent on support
Use the unit lesson section to teach it explicitly, not Daily Review.
Most students are secure, but the same smaller group persists
Keep whole-class Daily Review; use the unit lesson materials with that group specifically.
Foundation
Build foundations for this skill.
PPN03W Counting and place value 2Use this when Pre-Primary students need work on ordered position before moving to less-supported number-line tasks.
PPN03W Counting and place value 2 (links to the Australian Curriculum unit FN03A in Ochre)
Builds prerequisites for magnitude estimation: number tracks to 20, missing numbers, one more/one less, and ordering positions.
Number-track lessons (10–11), one more/one less (7–8) and ordering (9).
PPN06W Counting and place value 3Not yet written. Ochre has scheduled the equivalent unit (FN06A) for release in Term 4 2026 — check back once it is published.
This unit is not yet available in Ochre. Based on the Daily Review Schedule, it will include an early lesson on ordinal position on a number track, a useful precursor to number-line estimation. Until release, use PPN03W and the Daily Review deck.
Will support ordinal position on a number track — a useful precursor to number-line estimation.
Number–Place Value Daily Review deckUse this when students have already been taught the relevant number-position skill and need reactivation or practice.
Daily Review Topic Deck: Number – Place Value
Practice with ordered position, number tracks, hundred charts, two-digit representations, one more/one less and comparison.
Year 1
Extend this skill through Year 1.
1N01W Counting and place value 1, Lessons 12–13Use this when Year 1 students need teaching or reteaching with number location, ordered position, benchmarks, 100-chart patterns or number-line placement.
1N01W Counting and place value 1, Lessons 12–13 (links to the Australian Curriculum unit 1N01A in Ochre)
This is the primary Year 1 Ochre resource for number position and location. Teaches locating numbers on a 100 chart and locating numbers to 100 on a number line.
Lessons 12–13.
- If students do not understand number order or location → use this card.
- If students understand order but need practice → use the Number–Place Value Daily Review deck.
- If students are working on movement or distance for addition/subtraction → use 1N06W Lessons 1–3 instead.
1N03W Counting and place value 2Use this when students need reinforcement of two-digit number structure before or alongside number-line location work.
1N03W Counting and place value 2 (links to the Australian Curriculum unit 1N03A in Ochre)
Provides secondary support for magnitude estimation through two-digit numbers, one more/one less, and place-value representations.
Supports number magnitude but does not replace 1N01W Lessons 12–13 for number-line/location teaching.
1N06W Addition and subtraction 3, Lessons 1–3Not yet written. Ochre has scheduled the equivalent unit (1N06A) for release in Term 4 2026 — check back once it is published.
This unit is not yet available in Ochre. Based on the Daily Review Schedule, it will cover counting on, counting back, and finding distance between numbers on a number line within 20 — useful only for number-line movement, not magnitude estimation itself. Until release, use 1N01W Lessons 12–13 for magnitude estimation.
Will support movement and distance on a number line within 20, such as counting on, counting back, or finding the distance between numbers.
Number–Place Value Daily Review deckUse this when students have already been taught the relevant number-position skill and need reactivation or practice.
Daily Review Topic Deck: Number – Place Value
Practice with ordered position, number tracks, hundred charts, two-digit representations, one more/one less and comparison.
This section is for teachers using Ochre units as part of Tier 1 mathematics instruction in Australian Curriculum v9.0 settings.
Use Ochre unit lessons when students need teaching or reteaching. Use Ochre Daily Review when students have already been taught the skill and need practice, reactivation or fluency-building.
Step 1: Where does this sit in your teaching sequence?
The skill has not yet been taught and is coming up soon
Let the scheduled Ochre lesson address it. Consider brief pre-teaching for students flagged by ENSSA.
The skill has not yet been taught and is scheduled much later this year
Consider bringing the relevant lesson section forward for flagged students only — check prerequisite lessons first.
The skill has already been taught
Go to Step 2 below.
The skill was taught a while ago, last term or last year
Start with Daily Review as a quick reactivation and accuracy check. If students are still inaccurate, go to Step 2.
Step 2: How are students performing right now?
Use this once you’ve confirmed the skill has already been taught.
Students are inaccurate or unsure
Use the Ochre unit lesson section first — not Daily Review.
Most students are inaccurate
Reteach the relevant modelling/guided-practice section to the whole class.
A few students are inaccurate but most are secure
Use the lesson section for small-group reteaching with flagged students only.
Students are accurate but slow or inconsistent
Use Daily Review — do not run a full reteach.
Has this skill been introduced?
This only asks about timing. Whether the class is accurate is something Daily Review over the next few days will show; it does not need to be judged in advance.
Yes
Use the Daily Review resource below, every day, for an initial five consecutive instructional days, regardless of how accurate the class is assumed to be.
No, but it is coming soon
Do not start Daily Review yet. Read the background sections (Teaching guidance; Vocabulary, representations and stem sentences) and preview the unit lesson below now, ahead of when it is scheduled.
No, and it is not scheduled soon
Check curriculum sequencing and prerequisite knowledge. Consider brief, targeted pre-teaching for the students ENSSA flagged, not a full classwide response ahead of schedule.
After five days of Daily Review
One brief daily note is enough: accuracy, independence and efficiency, not a per-student written record.
Clear improvement, not yet secure
Continue the same Daily Review resource.
Most accurate and increasingly efficient
Continue Daily Review as ongoing cumulative practice; no full reteach is needed.
Most students remain inaccurate or dependent on support
Use the unit lesson section to teach it explicitly, not Daily Review.
Most students are secure, but the same smaller group persists
Keep whole-class Daily Review; use the unit lesson materials with that group specifically.
Foundation
Build foundations for this skill.
FN03A Counting and place value 2Use this when Foundation students need work on ordered position before moving to less-supported number-line tasks.
FN03A Counting and place value 2
Builds prerequisites for magnitude estimation: number tracks to 20, missing numbers, one more/one less, and ordering positions.
Number-track lessons (10–11), one more/one less (7–8) and ordering (9).
FN06A Counting and place value 3Not yet written. Ochre has scheduled FN06A for release in Term 4 2026 — check back once it is published.
This unit is not yet available in Ochre. Based on the Daily Review Schedule, it will include an early lesson on ordinal position on a number track, a useful precursor to number-line estimation. Until release, use FN03A and the Daily Review deck.
Will support ordinal position on a number track — a useful precursor to number-line estimation.
Number–Place Value Daily Review deckUse this when students have already been taught the relevant number-position skill and need reactivation or practice.
Daily Review Topic Deck: Number – Place Value
Practice with ordered position, number tracks, hundred charts, two-digit representations, one more/one less and comparison.
Year 1
Extend this skill through Year 1.
1N01A Counting and place value 1, Lessons 12–13Use this when Year 1 students need teaching or reteaching with number location, ordered position, benchmarks, 100-chart patterns or number-line placement.
1N01A Counting and place value 1, Lessons 12–13
This is the primary Year 1 Ochre resource for number position and location. Teaches locating numbers on a 100 chart and locating numbers to 100 on a number line.
Lessons 12–13.
- If students do not understand number order or location → use this card.
- If students understand order but need practice → use the Number–Place Value Daily Review deck.
- If students are working on movement or distance for addition/subtraction → use 1N06A Lessons 1–3 instead.
1N03A Counting and place value 2Use this when students need reinforcement of two-digit number structure before or alongside number-line location work.
1N03A Counting and place value 2
Provides secondary support for magnitude estimation through two-digit numbers, one more/one less, and place-value representations.
Supports number magnitude but does not replace 1N01A Lessons 12–13 for number-line/location teaching.
1N06A Addition and subtraction 3, Lessons 1–3Not yet written. Ochre has scheduled 1N06A for release in Term 4 2026 — check back once it is published.
This unit is not yet available in Ochre. Based on the Daily Review Schedule, it will cover counting on, counting back, and finding distance between numbers on a number line within 20 — useful only for number-line movement, not magnitude estimation itself. Until release, use 1N01A Lessons 12–13 for magnitude estimation.
Will support movement and distance on a number line within 20, such as counting on, counting back, or finding the distance between numbers.
Number–Place Value Daily Review deckUse this when students have already been taught the relevant number-position skill and need reactivation or practice.
Daily Review Topic Deck: Number – Place Value
Practice with ordered position, number tracks, hundred charts, two-digit representations, one more/one less and comparison.
Intervention resources (Tier 2 & Tier 3)
Targeted supports for students or small groups when classwide teaching is not enough.
Intervention resources
The Ochre Intervention Modules are Tier 2/3 resources, built on the same Foundation–Year 2 Ochre content already used for Tier 1, for students who need more than classwide or targeted small-group support.
No Ochre Intervention Module currently targets this skill directly
The published modules cover counting, numeral recognition, number sequence, magnitude comparison, decomposing numbers, and addition and subtraction facts, but none includes a genuine unlabelled benchmark-placement task, which is what magnitude estimation assesses.
- Module 2's ordering-on-a-number-track content (Lessons 18–31) is adjacent because it uses the same linear representation, but it is not a direct match. Treat it as an interim option only, with that caveat stated.
- Otherwise, continue with small-group Explicit Instruction Routines, vary the representation, or involve learning support directly.