Mentally add/subtract 1-digit numbers - Teaching Presentation - Year 3

This presentation provides two days of teaching that cover the objectives:

• Add 1-digit numbers to 3-digit numbers.
• Subtract 1-digit numbers from 3-digit numbers

It includes starter activities, whole class teaching, group activities, practice sheets and mastery questions. It can be used on a variety of interactive whiteboards.

Day 1 Teaching
Display 347 + 5. Discuss different strategies to find the answer. Encourage children to use number patterns and knowledge of facts, e.g. 7+5 = 12, so 347 + 5 = 352, or ‘bridging’ the next multiple of 10, i.e. 347 + 3 + 2. Repeat with 236 + 7 and 878 + 6. Then repeat to cross 100s, e.g. 498 + 4.

Day 2 Teaching
Write 342 – 6 = 339. Is this correct? How do you know? We can solve this using number facts: 12 – 6 = 6, so 342 – 6 = 336. Also use bridging to do 342 – 2 – 4. Repeat with 352 – 7. Ask children to write two other subtractions that involve crossing a multiple of 10. Choose some to solve as a class.

This teaching is part of Hamilton’s Year 3 Addition and Subtraction block. Each Hamilton maths block contains a complete set of planning and resources to teach a term’s worth of objectives for one of the National Curriculum for England’s maths areas.