Large number estimation as a vehicle to promote mathematical modelling

This article presents a teaching experiment study in which year 2 students compare city and town based on population estimates. The activities are presented to them as Fermi problems and require an analysis of the reality that allows the identification of sub-problems that the students can face. The students' products are analysed from the perspective of mathematical modelling and it is observed that the students develop their own mathematical methods to make the required estimates. Learning opportunities are identified when students require concepts and procedures that have not yet been worked on. The results show that estimation acts as a facilitator for the generation of mathematical models that allow students to connect their real-world knowledge with new mathematical learnings. In the conclusions, the implications of the use of Fermi problem sequences to initiate mathematical modelling and connecting mathematical and extra-mathematical knowledge about social problems in the first years of Primary Education are discussed.