From your class dashboard it is easy to see the project track for a specific lesson by clicking on the "+" under the lesson name.
This will open up the detail view for all of your students and allow you to click on any circle to see the student's code for that activity.
In this example, clicking on the red circle will open the activity so that you can see the student's code and investigate why they didn't get full points for the activity. In this case, the student went forward without completing the debugging activity.
See How do I find the solution to an activity? to learn how to compare the student's code to the answer key.