Sample work Mathematics K–10 Stage 2: Recording my strategies

Description of activity

Students solve addition and subtraction problems and record their strategies.

1. Students solve the following problem mentally and then record the strategy they used.
   34 + 17
2. Students repeat the process for the following problems:
   73 – 25
   63 + 29
   162 – 69

The suggested time allocation for this activity is 30 minutes.

Context

Students have had practice discussing and recording a variety of strategies for mental computations.

Outcomes

MA2-1WM uses appropriate terminology to describe, and symbols to represent, mathematical ideas

MA2-2WM selects and uses appropriate mental or written strategies, or technology, to solve problems

MA2-3WM checks the accuracy of a statement and explains the reasoning used

MA2-5NA uses mental and written strategies for addition and subtraction involving two-, three-, four- and five-digit numbers

Criteria for assessing learning

(These criteria would normally be communicated to students with the activity.)

Students will be assessed on their ability to:

• use appropriate mental strategies to solve addition and subtraction problems
• explain their reasoning using mathematical terminology