Despite curriculum expectations, many students, including a disproportionate number of girls, do not 'just know' (retrieve) single-digit addition facts by Year 3. The current study employed structured interviews to explore which strategies Year 3/4 students (n = 166) used when solving more difficult addition combinations. Results revealed that…

In Asia, some children are taught a calculation technique known as the 'mental abacus'. Previous research indicated that mental abacus experts can perform extraordinary feats of mental arithmetic, but it disagrees as to whether the technique improves working memory. The present study extended and clarified these findings by contrasting performance…

This paper provides insight about the development of addition and subtraction strategies for nearly 22,000 Australian primary school children in 2016. The children were each assessed by their teacher using a task-based assessment interview that identified the strategies they used to mentally perform addition and subtraction, and matched these to a…

Guidelines are presented for modifying basic instruction of subtraction facts for elementary level learning disabled students. A detailed case study is used to illustrate a five-step structured program: (1) find a way to work it out; (2) add to check; (3) learn the partner facts; (4) study families of facts; (5) review and practice. The selection…

Literature at national and international levels argues the importance of including mental computation in a mathematics curriculum that promotes number sense. However, mental computation does not feature in importance in the current Queensland mathematics syllabus documents. Hopefully, with the writing of a new mathematics syllabus, mental…

Estimation is an important skill for everyday living. Good estimators usually have a sound knowledge of basic facts, understand place value and use a variety of strategies to make their estimates. This paper describes an activity which is designed to provide students with opportunities to practice their rounding strategies with addition and…

This article presents an example of a versatile multi-solution problem that can be used right across the primary years. The basic problem is: "Noah saw 16 legs go past him into the Ark. How many creatures did he see?" Any even number can be used, although, 2 legs allows only one answer and with 16 legs there are already 14 different…