• Explore ratio and scale using ‘best buy’ scenarios.
• Develop understanding of systems of measurement and conversion of units.
• Relate ratios to scales on maps.
• Provide entertaining lesson material, with opportunities for further exploration.
• Demonstrate a practical, problem-solving approach.

After watching the programme, students should:

• Understand simple methods of comparing values given in different units.
• Be familiar with methods of calculating a price given a unit rate.
• Appreciate that standard measures are often arbitrarily defined, but provide a useful basis for comparing quantities.
• Recognise that scales on maps and drawings are expressed as ratios, and that these can be used to calculate real distances.
• Understand that converting between units allows comparisons to be made, and that unit ratios are useful in this.
• Be aware that the metric system is one of many systems that have evolved to allow us to compare and calculate physical quantities.