By the end of the lesson, students will be able to:[list=1][*]Define the [b]median[/b] of a triangle.[br][/*][*]Identify the medians in a given triangle.[br][/*][*]Draw the medians and locate the [b]centroid (G)[/b].[/*][*]Explore the relationship between the medians and the centroid using a GeoGebra animation.[br][/*][/list]

[*]Definition: a [b]median[/b] of a triangle is the segment joining a [b]vertex[/b] to the [b]midpoint of the opposite side[/b].[/*][*]Properties:[list][*]The three medians are [b]concurrent[/b] (they meet at one point).[br][/*][*]The common point is called the [b]centroid (G)[/b].[br][/*][*]The centroid divides each median in the ratio [b]2:1[/b], with the longer part from the vertex.[br][/*][/list][/*]

[table][tr][td][b]1. Introduction[/b][/td][td]Teacher shows a triangle and asks: “How can we divide it evenly?”[/td][td]5 min[/td][/tr][tr][td][b]2. Announcing topic[/b][/td][td] “Today we’ll learn about medians and the centroid.”[/td][td]2 min[/td][/tr][tr][td][b]3. New content[/b][/td][td] Explain definition, draw medians on board or GeoGebra.[/td][td]10 min[/td][/tr][tr][td][b]4. Practice[/b][/td][td]Students draw triangle and medians, checking intersection point.[/td][td]10 min[/td][/tr][tr][td][b]5. Digital activity (GeoGebra)[/b][/td][td][b]GeoGebra animation:[/b] dragging vertices to observe centroid movement.[/td][td]10 min[/td][/tr][tr][td][b]6. Consolidation[/b][/td][td]Discussion: What is the ratio along the median?[/td][td]8 min[/td][/tr][tr][td][b]7. Assessment[/b][/td][td] Short task: “Draw triangle ABC, mark midpoints, draw medians, and label centroid G.”[/td][td]5 min[/td][/tr][/table]

[*]Methods: guided discussion, problem-solving, demonstration, practical activity.[br][br][/*][*]Tools: board, ruler, set square, notebook, [b]GeoGebra animation (centroid visualization).[/b][br][/*]

Draw two triangles (isosceles and scalene) and draw their medians. [br]What do you notice about the centroid’s position?[br][br]