Centrepeace in paignton are offering a 2 day web design course, covering HTML / CSS and Java Script, please see their website for more information
http://centrepeace.org.uk/1/post/2014/07/learn-web-design-centrepeace.html
Download pdf poster below.
If you are under 11 then something similar could be offered as part of code club , Please get in touch with centre peace directly and mention code club.