¿Cómo podemos averiguar si Limpics es un fraude? Aprendiendo a diseñar investigaciones en educación secundaria

This paper presents a task designed to introduce 9th grade students (14-15 years old) to planning investigations in the Chemistry laboratory. We used a context related to everyday life: an enterprise committee has just launched a campaign in schools in which they ask students to help them to unmask another who has announced a very efficient detergent called Limpics. To help students in planning the investigation, they were provided with coloured cards containing some questions. Their answers to these questions following a particular order will compose the planning. The analysis consists of examining students' written designs (N = 20) depending on their content and adequacy to solve the investigation. The main results point to short and little precise designs.