Some different types of spelling activities here. All with a focus on learning rather than just being tested. For example, students learn to look for words within words, or practice spelling with a Look, Say, Cover, Write and Check program.
The second edition of Support for Spelling offers support for teachers wanting their pupils to become fluent and effective writers; accurate spelling is a means to that end. Competent spellers need to spend less time and energy in thinking about spelling to enable them to channel their time and energy into the skills of composition, sentence structure and precise word choice.
Brilliant! Gets you started with writing. Set yourself a target - how many words / how many minutes and start writing. If you pause you start to lose words you've already written.
Free version of Word Magnets. Really useful especially if you have an interactive whiteboard. Lots of different ways of arranging letters into words, categories, order, etc. And of course you can arrange whole words too. (Don't click on the Word Magnets 2 link unless you want the paid-for site licence - but if you do it's a great site to support)
Be warned - this is compulsive! Test your spelling. All sorts of new features, eg it notes the mistakes you make and makes a special spelling bee up for you - just with your mistaken words in it.