Evidence of implemented anticipation in mathematising by beginning modellers

Data from open modelling sessions for year 10 and 11 students at an extracurricular modelling event and from a year 9 class participating in a programme of structured modelling of real situations were analysed for evidence of Niss’s theoretical construct, implemented anticipation, during mathematisation. Evidence was found for all three proposed aspects. With respect to Niss’ s enablers of ideal mathematisation explaining unsuccessful mathematisations, flaws in the modelling of the year 10–11 students were related to the required mathematics being beyond the knowledge of the group members or poor choice of the particular mathematics to use in the modelling context; whilst unsuccessful attempts at mathematisations in the year 9 class were related to inability to use relevant mathematical knowledge in the modelling context. The necessity of these enablers as requisites for modelling, particularly in a classroom context, needs further investigation.