This software makes it easier to use the R language. It includes a code debugger, editing, and visualization tools.
This is a web application framework for R, in which you can write and publish web apps without knowing HTML, Java, etc. You create two .R files: one that controls the user interface, and one that controls what the app does. The site contains examples of Shiny apps, a tutorial on how to get started, and information on how to have your apps hosted, if you don't have a server.
This online booklet, Start Teaching with R, by Randall Pruim, Nicholas J. Horton, and Daniel T. Kaplan comes out of the Mosaic project. It describes how to get started teaching Statistics using R, and gives teaching tips for many ideas in the course, using R commands.