Project Launch and Exploration - Begin with a visit to a local bridge or examine images and videos of famous bridges, focusing on design elements. Discuss the role of geometry in bridge construction, introducing the Triangle Sum Theorem and its application in bridge design. Encourage students to brainstorm and sketch initial ideas for their bridge designs. (45 min)

Introduction to Triangle Sum Theorem - Facilitate a mini-lesson on the Triangle Sum Theorem, using interactive examples and activities to ensure understanding. Discuss how this theorem can be applied to ensure the structural integrity of bridges. (45 min)

Design Planning and Sketching - Students will develop detailed sketches of their bridge designs, incorporating the Triangle Sum Theorem. They will use peer feedback to refine their sketches, fostering self-directed learning and collaboration. (45 min)

Materials Exploration and Selection - Introduce students to different materials available for constructing their model bridges. Discuss the properties and strengths of each material and guide students in selecting appropriate materials for their designs. (45 min)

Bridge Construction Part 1 - Begin constructing the model bridges using selected materials. Students will work collaboratively in groups, applying their understanding of the Triangle Sum Theorem to ensure their designs can support weight. (90 min)

Bridge Construction Part 2 and Testing - Complete the construction of the model bridges. Conduct initial tests to evaluate the structural integrity and weight support of each bridge. Provide time for reflection and revision based on test results and peer feedback. (45 min)

Reflection and Documentation - Students will document their design process, including sketches, calculations, and reflections on what they learned. They will prepare to present their model bridges and explain their design choices, problem-solving strategies, and how they addressed feedback to refine their work. (45 min)