Interactive code editor for r scripts

Hi, I'm new here. I didn't know exactly to what category my question belongs.

I'm searching for a interactive tool for a teaching/learning project. The students should be able to try out R-Scripts in a kind of web-based sandbox. So I need a code editor similar to jsfiddle for R-Scripts that I can integrate into the web. In addition, the idea is that the students can also use it to submit their scripts for grading. The tool must be open source and free.

So far I have only found openopu.org.
Do you have any ideas?

Thanks previously!

Hello
I have found two aproximations of what you want.

In any case you still can use:

Colab may be a bit tedious, but, can be combined with classroom for teaching.