Designing a bath mat
Following work on friction, and earlier work on materials and properties, the pupils were asked to apply what they knew to design a non-slip, absorbent bath mat for a family.
For continuation in a later lesson, the pupils looked at consumer reports and produced individual plans for practical comparisons of friction provided by different mats when wet and dry, involving measurement of forces. They later worked with partners, deciding together which method they would actually follow.
When asked about what she meant by the statement that the mat was made of rubber because ‘it produces heat’ she explained that, ‘it makes your feet feel warm’. The class had not done specific work on energy and energy sources, so her mistake is understandable.
In planning her practical to compare mats, Holly reported that she intended to use a forcemeter to drag a slipper along the mats, starting from a standstill in each case and moving a set distance. She planned to repeat this on wet and dry mats, using the same amount of water, spread evenly, for each wet mat.
- Discussion with partner and collaborative decision making on methods to be used, followed by the investigation of friction on different wet and dry mats.
- Investigation of absorbency of different proposed materials.
Holly uses scientific ideas in her descriptions, and recognises the application of the idea of friction. For her planned investigation she identifies variables, makes relevant decisions about fair testing, and chooses appropriate equipment.