Most universities will have their own scholarship / bursary schemes and students should search for them for the universities they hope to attend. The Scholarship Hub seems to be a really useful website for this.
Here’s a list of other scholarships / grants which A-level students may want to look into (I’ll be updating this post as I stumble across other useful links):
The Ogden Trust – scholarships for 6th Formers studying Physics and Physics undergraduates
Range Rover Evoque WISE Scholarship (women) – £1000 per year for 3 years of degree
IET Diamond Jubilee Scholarships – at least £1000 per year of degree, up to 4 years.
BP STEM Scholarships of £5000 available at Durham University, Imperial College London, University of Bath, University of Birmingham, University of Cambridge, University of Manchester, University of Nottingham, University of Oxford, and University of Strathclyde – apply during first term of university.