Exploring Density in a New Way: A Problem-Solving Activity with Increasing Complexity, Based on Length Measurements

This work presents a problem-solving path structured to offer challenges of gradually increasing difficulty. Students in their third year of Italian high school are progressively presented with challenging problems related to determining the density of liquids. This quantity is determined by the students in four steps through the measurement of specific lengths and the application of Stevin's law. The activity, lasting 2 h, was carried out in its entirety within a chemistry laboratory setting. It necessitates only a limited quantity of materials and relies on a few fundamental theoretical concepts. Throughout the activity, students demonstrated increasing levels of attention and enthusiasm from one challenge to the next, even in the case of students who are generally less inclined toward scientific subjects and who have trouble finding solutions to problems. The students worked individually, and the instructor guided the learning process in a personalized manner for each student.