BBC Learning - http://www.bbc.co.uk/learning/coursesearch/ - This site is old and no longer updated and yet there's so much still available, from language learning to BBC Bitesize for revision. No TV licence required except for content on BBC iPlayer.
Cbeebies Radio - https://www.bbc.co.uk/cbeebies/radio - Listening activities for the younger ones.
Blue Peter Badges - https://www.bbc.co.uk/cbbc/joinin/about-blue-peter-badges -If you have a stamp and a nearby post box.
BBC Teach - https://www.bbc.co.uk/teach - The BBC has a whole website dedicated to helping Parents & Carers who are teaching their children at home. These include videos and interactive lessons.
BBC Bitesize - https://www.bbc.co.uk/bitesize - The BBC had lots of free videos and helpful topics on a number of topics.