Hi Padraic,
Like Conor above, working in a Dublin school allows you to look at and tackle this issue in slightly different ways. One thing which I find useful in terms of ‘investigating and experimenting’ is to look at the air-quality index that can be found on many reputable sites. Locations across Ireland and cities globally could be tracked over a period of time. Projects can then look at the reasons for poor/good air quality and measures that can be put in place to address this. Having the research done adds an extra layer of relevance to the project and one that has worked well in the past.