I'm beginning to use the captain-teach system, developed at Brown University, to facilitate peer review while an assignment is in progress. I'm going to pilot using this system on two of my 10th grade sections currently enrolled in AP CS Principles. I have a third section that is struggling with engagement and behavior that I am not going to try a new system with in the middle of the year.
AP CS Principles requires students to write about a computing innovation and about an original programming as part of the final course assessment. However, during the administration of these two tasks (8 hours for one, 12 hours for the other) I am not permitted to give students feedback on their work. At the same time they are encouraged to collaborate with each other.
Captain-teach accepts student submissions and distributes them to classmates for peer review. Reviewers can add in-line comments and provide feedback on likert scale determined by the teacher. The system is agnostic about the medium in which students are working, so I can use the same system for developing programs as for developing the documentation and written responses.
Our next unit is analyzing data. Students will need to be able to formulate questions that are answerable with a given data set. Captain-teach should provide a great way for students to give each other feedback on those questions.