Getting your students to think like a designer can help you reach your technology learning objectives. One no-cost task involves a thought experiment and a piece of technology -- any product, system or piece of equipment. Ask your students to examine the product while predicting the specifications -- criteria or constraints -- that the designer had in mind while creating it. For instance, when designing a lampshade, the user must be able to have access to the lamp's on-off switch without touching the lit bulb, which could result in burns. A lid of a bottle must be tight enough to maintain a partial vacuum seal, yet still be easy enough for an elderly person with a weak grip to open the jar. A sign must use a font that can be read by older people who cannot focus at close distances. A staple must be strong enough to go through many sheets of paper, but malleable enough so that removal does not break a fingernail.
Some specifications are less obvious. For instance, toilet paper must be strong enough to do its initial work (not shred when a person blows his nose), but must also be able to dissolve after a few seconds when placed in water so that the waste treatment plant does not get clogged with mounds of paper. A pen's ink must be permanent enough to stay on paper, but not so permanent that it cannot be washed out when it stains a blouse or shirt. The material in a car seat must be attractive, but also must be able to look presentable even after surviving numerous spills of various liquids over the many years of a car's lifetime.
Ask you students to pick a favorite products, and then infer its specifications. With some practice, they should be able to focus on key aspects of any product, which is important when they are asked to produce their own designs.