🔢 Primary Maths & Science Games · Grade 4 · Decimal place value and the decimal point
Decimal Place Value: Build, Compare and Move the Decimal Point
The two classic decimal mix-ups are "more digits means bigger" and "which way does the point move?". Build the number, see it as blocks and watch the digits slide, and it becomes clear why 0.5 > 0.45 and 3.6 × 100 = 360.
- Free, no sign-up
- Ad-free play area
- Tablet friendly
- Parent mode
- A4 worksheet
- 4 levels
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How to play
- In Explore, tap ▲▼ on the place-value chart and watch the block model and the reading change together.
- Press ×10, ×100, ÷10 and so on to watch every digit slide while the decimal point stays put.
- Levels: build a decimal, place value and units, comparing, and moving the point.
Curriculum unit
Primary maths, grades 3–4: decimals as tenths and hundredths, reading and writing decimals, comparing, and multiplying or dividing by 10, 100 and 1000 (PEP textbook, grade 4, unit 4).
For parents and teachers
Mistakes are grouped as "more digits = bigger", wrong direction, wrong number of places and unclear units, and the worksheet targets the weakest group.
FAQ
Are 0.5 and 0.50 the same?
Yes. Adding or removing zeros at the end of a decimal does not change its value.
Why is 0.5 bigger than 0.45?
Compare the whole part, then the tenths: 0.5 has 5 tenths and 0.45 has only 4, so 0.5 is bigger, whatever the number of digits.
What happens when the decimal point moves right?
Moving it 1, 2 or 3 places right makes the number 10, 100 or 1000 times as big; moving left makes it 1/10, 1/100 or 1/1000 as big.