I have recently realised how fortunate we are in the UK to have a lot of opportunities to have 2 jobs or have a side hustle whilst at work or school.  This country offers a lot of opportunities to make extra money on the side. You can;

1. Look for traditional work on the side like working in restaurants, bars, call centres, car washes (if you can brave the weather)
2. Take the tech entrepreneurial route through platforms like eBay, Amazon, Gumtree, Shopify, to name a few
3. Another growing trends in also involves virtual work on a per job basis via sites like Fiverr. Where you can use your skills, web design, copy writing, translation etc

In short you can use your time wisely by earning extra cash. Some of these are growing opportunities that can turn into full time work.