- Home
- Canvas Guide
Partial Progress - Circles (browser only)
Calculations
Objectives
To place 2-digit numbers on a number line.
Resources
Abacus Workbook 3 | 📄 0-9 digit cards
Vocabulary
estimate | position
Today's Lesson
Introduction
Draw a line from 0–100 with only 0 and 100 labelled and no other marks.
Ask:
- Where should we mark 47?
- What number might it be useful to place on the line to help?
Discuss how it would be helpful to mark on 50 as this is a number that is close to 47.
Ask:
- Where is 50 on this line?
Agree that 50 is halfway, so 47 is a little bit before this.
Ask:
- Where is 27 on this line?
- What number might it be useful to place on the line to help? (25 possibly, or 30)
- And where is 25 (or 30) on the line?
Continue to challenge your student by asking:
- Where is 70 on this line?
- Is it nearer 50 or 100?
Continue with similar questions until you have marked on all multiples of 10.
This video will help to demonstrate estimating positions of some 2-digit numbers on a 0-100 number line.
Next, place a sheet of paper with a large 0 written on it at one end of the table, and a sheet of paper with a large 100 written on it at the other end of the table, so they are far away from each other.
Secretly write a number (for example, 57) on a sheet of paper and place it face-down roughly where it should go in between the 0 and 100. Ask your student to guess what they think the mystery number might be.
Repeat the above task so your student has a few goes at this.
Say:
- I can re-number the ends of the line with two multiples of 10. Which do you think would be helpful?
Write these (50 and 60) on two sheets of paper to replace the 0 and 100.
Ask your student to adjust the position of the 57 accordingly.
Repeat with different numbers.
For example, where would 38 go if it was placed in between 30 and 40?
Main Activity
Shuffle a pack of 1–9 digit cards (taken from the 📄 0-9 digit cards).
Your student should take two cards and discuss the 2-digit numbers that can be made using these digits.
Ask them to sketch their own 0–100 line along the length of a page and decide where their numbers should be written. An A4 book with 1cm squared paper is long enough to accurately sketch a landmarked line with 2 squares for every division of 10.
Estimate the position of each number, then mark on other numbers to help check the position, for example, 50 or other multiples of 10.
Repeat with other pairs of numbers on the same line.
More lines can be sketched to avoid cluttered recording.
Encourage accurate estimation.
Ask:
- Where does 43 belong?
- Where is that in relation to halfway?
- Which 10s numbers would it sit between?
- Which is it closer to?
Extra Support
Carry out the activity as above but use a 📄 0-100 landmarked line.
Your student can then try sketching their own lines.
Workbook
To help your student consolidate their learning from today, please ask them to complete the activities on pages 2 and 3 of Abacus Workbook 3.