Mental strategies for addition and subraction

Research results to note:

In a research project with children aged 6-9 years in Queensland, Australia, Heirdsfield and Cooper (1998) found that introducing pupils too early to formal written algorithms for addition and subtraction limits their willingness and ability to develop a range of mental strategies and a good number sense. When presented with a calculation written in horizontal format and invited to find the answer mentally, the majority of such pupils tended to use a mental strategy based on the formal written method. Interestingly, the pupils showed a greater range of mental strategies when the calculation was presented as a word problem. Clearly, the range of addition and subtraction structures embedded in real-life situations suggests different ways of doing the calculations, some of which they had not specifically been taught in school. The researchers also found that pupils who were most successful in mental addition and subtraction had two key skills: very secure knowledge of number facts and a good sense of computational estimation.

Heirdsfield, A. and Cooper, T. (1998) ‘The architecture of mental addition and subtraction’, paper presented at the Annual Conference of the Australian Association of Research in Education, Brisbane, January.