Hi qu,

Unless your students save their code as a spin-off of the challenge, you unfortunately won't be able to view the code that they submitted. Once they save their work as a spin-off, you should be able to view their work on the Projects tab in your class.

If you create an assignment for the challenge, you should be able to see whether or not they've completed the challenge via the Scores tab. However, you still won't be able to view their code unless the create a spin-off.

I hope this helps! Please let me know if you have any additional questions!