The Tate Gallery for KidsThis is the website for The Tate Gallery. It has artworks to look at online but also fun ideas for making. There are some interactive art applications and quizzes too like: https://www.tate.org.uk/kids/games-quizzes/street-art
BBC Art Bitesize KS2The BBC has a set of videos for art. There is a great range which gives information about different artists as well as suggestions for activities
Art with Rob BiddulphSome brilliant short clips talking you through how to draw different things...from dogs to aliens!