Its £30 a year and covers Maths, English, Science, and 3 languages.
It is a good all round package and covers a good general range of topics.
The main thing is make sure you sort out which levels you want to work on with each subject during the trial. Once you have signed up, you only get 3 opportunities to change through the year, so its best to sort it out before you do pay.
I, as a parent really liked it. It was the first online tuition package I had found that wasnt overly expensive, but gave me feedback on how my DC were doing. there is a Parents section where you can see all the answers that they gave and the results. If they complete the task more than once, all results are recorded.
I liked the tests for maths as well, because it covered many strands I was able to build a picture of strengths and weaknesses. They also gave you the NC level of each question to help you.
There are also curriculum details on the site that show what each game is targetting.
I like the range of topics and the science section has been an excellent introduction into topics that DC dont/wont cover at school.
They didnt do much with the languages at all.
The topics dont cover every aspect of the curriculum but its certainly a good base and I strongly believe it has helped my kids.
Kids view - hard to get them on but they enjoy it once they are on. And, they do feel it has helped them hugely at school because when they start a new topic, they have had an introduction beforehand and it makes more sense for them.
The customer service is excellent and they always respond quickly to queries.
Me personally, I would recommend this site.
However, we have only worked on the Y4,5,6,6+ so cant comment about the earlier years.