Thanks to Tracy Batt for this lead – Educaplay is a ‘…platform for creating multimedia teaching activities’. They’re essentially designed for creating simple language exercises by the looks (see range of activity types below). They can be embedded in webpages for integration into larger web-based tasks. The one I tried (jumbled sentences) was easy to use – after a bit of orientation.
Click on either of the images to go to the sign up page (a bit confusingly referred to as sign-in here).