Are you interested in Planet Sherston?
Sherston is a name that you will have heard of; you may even be using some of their software titles in your school. They offer a free web service to schools called Planet Sherston. (There is also a premium account which is chargeable but the free product is also valuable) In Planet Sherston teachers can build tasks and assign them to individuals, groups, whole classes or even the whole school.
The 'Freemium' Account gives unlimited free access during the school day to all of the Curriculum Mapped resources for English, Maths & Science, along with many of the key features such as their 'Adaptive Learning Engine'. The activities are games based and adjust to the level of the child.
The service has been really popular since it’s launch at the end of 2014. More information can be found at - http://www.planetsherston.com