Begin with an engaging question: 'Have you ever wondered how your body gets rid of waste?' This will capture students' attention and introduce the topic of the excretory system.

Introduce the excretory system by explaining its role in waste removal and the main organs involved: liver, kidneys, and bladder.

Explain how the liver filters blood and produces urea, which is then processed by the kidneys.

Describe the process of urine formation and elimination through the kidneys, ureters, bladder, and urethra.

Watch the video 'All About Your Body' to understand how different body systems, including the excretory system, work together. This video provides a comprehensive overview of human anatomy and physiology.

Discuss the importance of each organ in the excretory system and how they contribute to maintaining a healthy body.

Conduct a model-building activity where students create a simple model of the excretory system using household items to visualize the process of waste removal.

Use diagrams to label the parts of the excretory system, reinforcing the function of each organ.

Assign students to write a short paragraph explaining how the excretory system helps in maintaining homeostasis.

Use the assessment 'The Excretory System' to evaluate students' understanding of the system's parts and functions. This assessment includes diagram labeling and written responses.

Have students share their models and paragraphs with the class, discussing what they learned about the excretory system.

Reflect on how the excretory system is similar to other systems in the body in terms of maintaining health and balance.

Encourage students to complete the 'Review – Human Body Systems' assessment to connect the excretory system with other body systems. This activity helps in understanding the interactions and roles of various systems.