Ancient Oven Efficiency

Overview

In this 70-minute lesson, Year 9 students will investigate the energy efficiency of traditional ground ovens used by Aboriginal and Torres Strait Islander peoples. They will engage with scientific concepts related to energy conservation, thermodynamics, and sustainability by designing and testing modern models inspired by these traditional ovens. This lesson integrates Indigenous knowledge with contemporary scientific inquiry, encouraging respectful acknowledgment of First Nations contributions to sustainable practices.

Australian Curriculum Alignment

Science Understanding

• AC9S9U05
  Apply the law of conservation of energy to analyse system efficiency in terms of energy inputs, outputs, transfers, and transformations, including cultural applications such as ground ovens used by First Nations Australians.

Science Inquiry Skills

• AC9S9I01
  Develop investigable questions, reasoned predictions, and hypotheses to test relationships and develop explanatory models relevant to energy efficiency and heat retention.
• AC9S9I02
  Plan and conduct valid, reproducible investigations including controlling variables and developing risk assessments, with ethical considerations regarding cultural heritage.
• AC9S9I03
  Select and use equipment to generate and record precise data, using digital tools where appropriate.
• AC9S9I06
  Assess the validity and reproducibility of methods, evaluating conclusions and identifying assumptions and uncertainties.
• AC9S9I07
  Construct arguments based on evidence and consider cultural protocols in accessing and using data, acknowledging First Peoples’ knowledge.

Science as a Human Endeavour

• AC9S9H04
  Examine how societal values influence scientific research, including Indigenous contributions to sustainable technologies.

Learning Objectives

By the end of this lesson, students will be able to:

• Explain the law of conservation of energy and apply it to ground ovens.
• Compare the energy efficiency of traditional ground ovens to modern insulated ovens.
• Design and construct a model of a ground oven using recycled materials, manipulating insulation and ventilation.
• Conduct experiments to investigate how insulation and ventilation affect cooking times and heat retention.
• Analyse data to draw conclusions about energy efficiency in their models.
• Respectfully incorporate Indigenous knowledge into scientific inquiry.

Resources Needed

• Recycled materials (cardboard boxes, aluminium foil, bubble wrap, old newspapers, empty cans, sticks, etc.)
• Kitchen thermometers or temperature sensors
• Stopwatch or timer
• Small heat source (e.g., heat pads, controlled safe heat source)
• Data recording sheets or digital devices for data entry
• Reference images and descriptions of traditional Aboriginal and Torres Strait Islander ground ovens
• Safety equipment (gloves, goggles)

Lesson Structure

1. Introduction and Context (10 minutes)

• Begin with a discussion on traditional Aboriginal and Torres Strait Islander ground ovens, highlighting their cultural significance and use in sustainable cooking practices.
• Introduce the concept of energy efficiency and the law of conservation of energy (AC9S9U05).
• Show diagrams or photos of traditional ground ovens and explain how heat is trapped and transferred.
• Pose the investigable question: “How do insulation and ventilation in a ground oven affect cooking time and heat retention?” (AC9S9I01)
• Briefly discuss ethical considerations and cultural respect in studying Indigenous technologies (AC9S9I02).

2. Hypothesis and Experimental Design (10 minutes)

• In pairs, students develop hypotheses related to how changes in insulation materials or ventilation holes might affect the oven’s heat retention and cooking speed.
• Guide students to plan an experiment using recycled materials to build a ground oven model (AC9S9I01, AC9S9I02).
• Discuss variables: independent (type/thickness of insulation, number/size of ventilation holes), dependent (temperature inside the model, cooking time), controlled (heat source, oven size).

3. Model Construction (15 minutes)

• Students construct their ground oven models using provided recycled materials.
• Encourage creative adaptation based on traditional designs but using safe, accessible modern materials.
• Advise incorporation of insulation and options for adjustable ventilation.

4. Experimentation and Data Collection (20 minutes)

• Place each model over a consistent, safe heat source.
• Measure and record temperature inside the oven at 5-minute intervals for 15-20 minutes (or keep track of ‘cooking time’ simulated via temperature milestones).
• Record data carefully, ensuring precision and consistency (AC9S9I03).
• Rotate groups if needed to observe multiple model variations.

5. Data Analysis and Discussion (10 minutes)

• Students graph temperature vs time for their models, identifying trends related to insulation and ventilation.
• Discuss the efficiency of their model ovens in retaining heat and potential real-world implications.
• Relate findings to the law of energy conservation and energy transfer processes (AC9S9U05).
• Facilitate reflection on how Indigenous knowledge contributes to contemporary sustainable practices (AC9S9I07, AC9S9H04).

6. Conclusion and Cultural Reflection (5 minutes)

• Students share key findings and reflect on the importance of respecting and integrating Indigenous scientific knowledge.
• Emphasise the relevance of traditional ecological knowledge in modern sustainable design.
• Highlight collaborative pathways between First Nations knowledge and science for environmental stewardship.

Assessment

• Formative assessment through observation of student engagement and application of scientific method during model construction and experimentation (AC9S9I02).
• Students submit a brief report or presentation including their hypothesis, method, data analysis, and conclusions that reference Indigenous knowledge respectfully and the scientific principles applied (AC9S3I06 adapted for Year 9).
• Evaluate understanding of energy conservation concepts and experimental design through targeted questions and data interpretation tasks (AC9S9U05, AC9S9I06).

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Extensions and Support

Extension Activities

• Investigate efficiency of electric ovens vs traditional ovens in terms of carbon emissions and sustainability.
• Explore other Indigenous cooking methods and their environmental impacts.
• Use digital simulations for modelling heat transfer in different oven designs.

Support for Diverse Learners

• Provide sentence starters and scaffolded planning templates for experimental design.
• Use group roles to engage students with different strengths (builder, recorder, analyst, presenter).
• Incorporate visual aids and mini-explanations on thermodynamics vocabulary.

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This lesson will not only deepen students’ understanding of scientific concepts and inquiry but also foster respect for First Nations Australians’ enduring scientific contributions and sustainable practices. The hands-on inquiry combined with cultural context aims to enrich student learning experiences and promote interdisciplinarity aligned with the Australian Curriculum (v9).