Malcolm found mathspace:

• Moderately improves attainment“Students have to show their methods and then usually has videos to help them through any problems they have.”
• Moderately improves teaching efficiency and productivity“Clear view of general misunderstandings from homework review and where their strengths lie.”
• Moderately reduces teacher workload“Marking is reduced and it helps target my planning for future lessons. Also allows students to be extended when they do an Adaptive assessment.”
• Slightly improves teacher knowledge and skills“Sometimes there are interesting ways of asking questions that I had not thought of before.”
• Moderately provides school data“We do use Mathspace in place of a written test on occasions, and the data is used in our reporting.”