Place Value of Decimals to Thousandths

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1 Getting Started
2 Watch and Notice
3 Try It Together
4 Sketch the Columns in Your Copy
5 Class Challenge
6 What Did We Notice?
7 What's Next
Pupil practice

1 - Getting Started ~4 mins

Look at this number written on the board: 0.001.

How many of these tiny amounts do you think we would need to make one whole? And how could we be sure we are right?

Write 0.001 on the IWB and give five seconds of quiet think-time before any hands go up. Take three hands-up answers, not open call-outs.

Listen for pupils who reason from the column name (thousandths, so a thousand of them) rather than guessing a round number. Revoice a strong answer: so it takes a thousand thousandths to make one whole, the same way it takes a thousand units to make a thousand.

👇 Mark your steps as done as you complete them.

+5 XP

2 - Watch and Notice ~9 mins

Illustration for Watch and Notice

0.4

Watch as we build this number in the columns. There are four tenths and nothing else. Where does the 4 sit?

0.27

This time there are two tenths and seven hundredths. We have moved one column further to the right.

0.305

Look hard at the hundredths column on this one. What do you notice sitting there?

2.408

Now we have a whole number and a decimal together: two units, four tenths, no hundredths, and eight thousandths.

Teacher Notes

Walk each example aloud, one at a time, pointing at the column the new digit lands in.

0.4 — name the tenths column; there is nothing in the other two decimal columns.
0.27 — move one column further right to the hundredths.
0.305 — pause on the zero in the hundredths column; ask 'what is that zero doing here?' before revealing it holds the place so the 5 stays in thousandths.
2.408 — show a whole number and decimal together, and read it as two and four hundred and eight thousandths.

👇 Mark your steps as done as you complete them.

+10 XP

3 - Try It Together ~11 mins

Today we build decimals together on the place-value chart. The columns are units, tenths, hundredths and thousandths. When a number is called, we place each digit in its column and then read the whole decimal back aloud, checking each column as we go.

Build the called decimal

Teacher Notes

This round is for talking it through together — pupils take turns at the board and the class agrees or corrects out loud.

Call a decimal (start with 0.6, then 0.38, then 0.207, then 1.504), have an individual pupil build it on the chart in decimal mode, and ask the class to check the live readout column by column before reading the whole number aloud.

Watch for the embedded-zero slip on 0.207 — pupils often skip the empty hundredths column and write 0.27 instead. Revoice: the zero is doing a job, it is holding the hundredths place so the 7 stays in thousandths.

+15 XP

4 - Sketch the Columns in Your Copy ~2 mins

COPYBOOK MOMENT

Illustration for Sketch the Columns in Your Copy In your maths copy, sketch four columns and label them U, t, h, th. Then write each of these decimals into the columns, one under the other, and underline the thousandths digit on each one.

0.4
0.27
0.305
2.408

Teacher Notes

Walk the room glancing at column labels and alignment, and check that the empty columns in 0.4 and 0.305 are left blank rather than skipped. No marking — this is whole-class copybook practice, not assessment.

+10 XP

5 - Class Challenge ~8 mins

Today we read these decimals together: 0.006, then 0.05, then 0.408, then 1.207, then 3.09. The zeros catch people out, so we will say each one aloud and build it on the chart before we check it.

Build the decimal

Teacher Notes

This round is the practice bank — pupils take turns at the board, check each answer, and the class confirms before moving on. Keep the board work brisk rather than over-explaining.

Each target steps up the zero-trap: 0.006 (only thousandths), 0.05 (only hundredths), 0.408 (zero hundredths), 1.207 (zero hundredths with a whole number), 3.09 (nine in the hundredths column with a whole number, no thousandths). For each one ask the class 'what is tricky about the zeros here?' before the pupil at the board presses Check.

+15 XP

6 - What Did We Notice? ~3 mins

MATHS TALK

Why is each column to the right ten times smaller than the one before it?

And here is one to just talk about, with no right answer to find: what do you think would change about our chart if each column were a hundred times smaller instead of ten?

Teacher Notes

Listen for pupils linking the decimal columns back to the whole-number columns — the same ten-times pattern, just running the other way. Revoice a strong answer: so the pattern never stops, it just keeps shrinking by ten each step.

The 'hundred times smaller' question is a what-if to stretch reasoning, not a new rule to teach — let pupils argue it out and head off any who think it would simply skip a column.

+10 XP

7 - What's Next ~3 mins

What we learned today

The three columns to the right of the point are tenths, hundredths and thousandths.
Each column to the right is ten times smaller than the one before it.
A zero in a decimal column holds the place so the other digits stay in their correct columns.

Coming up

Next we will use base-ten blocks to model thousandths, so you can see and hold how much smaller each column really gets.

Teacher Notes

Recap the three column names in order, then preview the block-modelling lesson. Keep this brief.

+5 XP

Pupil practice

Module 1 · Place Value, Decimals and the Number System Number

Lesson 2 · Place Value of Decimals to Thousandths

Download Activity Book page (PDF)

End of lesson

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Teacher Class Feed

1 - Getting Started ~4 mins

2 - Watch and Notice ~9 mins

0.4

0.27

0.305

2.408

3 - Try It Together ~11 mins

Build the called decimal

4 - Sketch the Columns in Your Copy ~2 mins

5 - Class Challenge ~8 mins

Build the decimal

6 - What Did We Notice? ~3 mins

7 - What's Next ~3 mins

What we learned today

Coming up

Unlock the full learning experience

XP