Use of preventative inhalers can be patchy which results in over-reliance on reliever inhalers - which means that the condition is not being managed as well as it should. The consequence is that asthma attacks may become more frequent or more severe.
Look at this BBC article http://www.bbc.co.uk/news/health-27257911 for more about the report.
For your 14-16s look at Breathing Made Easy. This CIEC resource will help your students understand the science and basic management of asthma.
Breathing Made Easy is also available through the NSLC STEM resource library: