65 SUBJECT Mathematics TOPIC FROM CURRICULUM GENERAL TOPIC: SUBTOPIC GEOMETRY AND MEASUREMENT Geometric concepts LEARNING OBJECTIVES Get to know and use Thales' theorem. ART EXPRESSIOSIONS/VISUAL FORMS USED Measuring the height of the Piran bell tower. SPECIAL REQUIREMENTS A stick of known height, a metre, a sunny day. MOTIVATIONAL STAGE TITLE OF THE LESSON Measuring height with Tales theorem (ratios / proportions). ISSUE/PROBLEM (society issue, issue that is seen relevant from pupils’ perspective, issue linked to some nature phenomenon or phenomenon from pupils’ everyday life) How to measure the height of a tall object with simple tools. INVESTIGATIONAL STAGE DESCRIPTION OF THE ACTIVITY Bell tower height measurement. TASKS By measuring the length of the shadow bars and the bell tower and calculating the length ratios, the height of the bell tower is calculated as the ratio of the height of the bar and the bell tower. First, the length of the shadow of the rod and the bell tower is measured and their ratio is calculated. The resulting ratio is used in calculating the height relative to the length of the rod. GOAL OF TASKS Calculated (measured) height of the bell tower. TEACHING METHODS: (creativeproblem solving, resource-based learning, inquiry-based learning, setting small groups, teamwork, experiential learning) Creative problem solving, pair work, independent work, research, experiential learning. CONSOLIDATION STAGE APPROACH/METHOD (discussion, argumentative debate, role-playing …) Discussion.