A case study of the influence of diagnostic information on a teacher’s planning for a Year 8 algebra lesson

With the emergence of online testing, data about students’ mathematical thinking is becoming more readily available to teachers in the form of diagnostic information. The availability of such data presents opportunities for teachers to use the data to inform their planning and teaching. The aim of this research was to investigate how diagnostic information, provided by an online system, impacted a teacher’s lesson planning for one Year 8 algebra lesson. The online assessment used to provide the diagnostic information in this research was the ‘Specific Mathematics Assessments that Reveal Thinking’ (SMART) test. The SMART tests system includes individual student diagnoses and teaching advice consisting of potential student difficulties and how to address these. In this case study, the teaching advice impacted the Year 8 mathematics teacher’s awareness of potential student misunderstandings, and resulted in the teacher changing their lesson plan on solving linear equations with pronumerals on both sides of the equation. The changes made included an emphasis on the gathering of algebraic like terms for explanations of solving equations with pronumerals on both sides of the equal sign. While broad generalisations cannot be made from this single case study about teacher planning, the findings suggest there are opportunities to help teachers better understand the developmental stages associated with learning how to solve linear equations, and the potential difficulties students may encounter. This study also allows for future research to be conducted on a larger scale about the impact of diagnostic information on teacher lesson planning.