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These resources have been reviewed and selected by STEM Learning’s team of education specialists for factual accuracy and relevance to teaching STEM subjects in UK schools.

Bag Alarm

This activity, suitable for a multi-lesson sequence or a single extended session, challenges students to design and prototype a simple motion-sensing alarm. The device is intended to prevent theft or the accidental picking-up of a bag.

Motion is sensed using the accelerometer built-in to the BBC micro:bit, while output is via a buzzer, piezo sounder, or by displaying text and symbols on the micro:bit LED array. Common applications of accelerometers are explained within the resources and accompanying video.

Students make a product analysis before creating their design. Guidance for programming the solution is provided, with sample code in the Block and Touch Develop editors.

An extension activity is provided, integrating the micro:bit into a personal heart-rate monitor product.

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