Online Learning Resources
GCSEPod is a fantastic resource for short podcasts and videos for GCSE. All KS4 students have a free subscription.
BBC Bitesize for KS3 has resources, quizzes and videos for all subjects
Free taster courses aimed at those considering Open University but everyone can access it. Adult level, but some e.g. nature and environment courses could well be of interest to young people.
Especially good for maths and computing for all ages but other subjects at Secondary level. (Note this uses the U.S. grade system but it's mostly common material).
Creative computer programming
Free to access 100s of courses, only pay to upgrade if you need a certificate in your name (own account from age 14+ but younger learners can use a parent account).
For those revising at GCSE or A level. Tons of free revision content. Paid access to higher level material.
Learn languages for free. Web or app.
Brilliant Club Youtube Channel
The Brilliant Club is an award-winning university access charity that works with schools and universities across the UK.