SMILE is a free application from Michigan State University that let’s you create, and then hosts for you online, numerous language development activities.
You can create clozes (fill-in-the-blank), drag-and-drop exercises, sequencing activities, and many more.
I personally think it’s the easiest online web application of its kind, both for students and teachers to use.
In addition, Michigan State has just released a group of new online activities that can be used in conjunction with SMILE. These free applications are called CLEAR. CLEAR allows you to use audio, video, and images with the exercises your create with SMILE. I’ve placed that link in the same place.