To understand what studying a subject is like at university, it is important that you read, watch and listen to materials beyond the school curriculum.
As well as helping to get a feel for your a subject, demonstrating that you have engaged beyond the school curriculum is crucial to a great UCAS application. If you are applying to the most selective universities, this will be seen as a requirement.
You will be in a strong position to write convincingly if you can refer to one or two key articles, podcasts or TED talks below that you found interesting.
Having wider experience of your subject will help you stand out!