1 - Getting Started ~3 mins
Number riddle time. I am thinking of a number with 6 tens and 3 units. What is it?
Now one with 3 tens and 6 units. Is that the same number?
2 - Watch and Notice ~7 mins
Three numbers on the hundred square. A digit is one of the symbols 0 to 9 that make a number.
For each riddle, find the row first (the tens), then count along (the units).
Here is the last number. Same digits as 63, but swapped. See where 36 sits next to 63. Why is 36 smaller? We will notice this together.
3 - Try It Together ~6 mins
We will shade each riddle number together.
First, two tens-and-units riddles. Tens for the row, then units along the row: 4 tens and 7 units; 8 tens and 0 units.
Next, hop on the square: one more than 29; ten less than 82.
Shade the riddle number
4 - Write Two Numbers in Your Copy ~2 mins
In your maths copy, write the number with 7 tens and 2 units, then the number with 2 tens and 7 units, one under the other.
- 7 tens and 2 units
- 2 tens and 7 units
5 - Class Challenge ~8 mins
Four riddles on the hundred square. Take turns to shade, then we check.
- 3 tens and 4 units: which row do the tens put you in?
- ten more than 58: one step straight down
- one less than 70: one step back
- 9 tens and 9 units: which row do the tens put you in?
Shade the riddle number
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