Attending lectures is a great way to be able to learn more about your favourite subjects, experience higher education and enhance your UCAS application.
If you are applying for a university which will require an interview lectures are an excellent way to display your enthusiasm for the subject to the admissions tutors.
Start by asking your individual subject teachers for advice on any particularly relevant lectures taking place that they are aware of.
Aside from that keep an eye on university websites for free public lectures.
Finally look on the Gresham College website. This is an education organisation which sources excellent academic speakers to lecture on almost all topics and subject areas. The lectures are always free, always held in London and are popular, interesting and accessible for all.