Sometimes our agenda in assigning a group project is precisely to help those students who find it challenging to develop the cooperative skills they will need to be successful in the workplace and the social world. If that is the case, it is important to structure the work clearly, provide defined roles for group members, monitor and support the group process during the project, and make it clear how the project will be evaluated based on individual and/or group effort and results.
If teaching and supporting cooperative group learning is not the main agenda, then I think it is important to offer an alternative, independent project as a differentiated option. As long as the learning targets for the assignment are clear to you, there will be another way for students to demonstrate their skills. Here's an example of a culminating project my students are just finishing for our Civil War integrated history and language arts unit. After studying the historical facts of the Civil War and reading Paul Fleischman's Bull Run as a model of writing from multiple perspectives, the majority of students opted to write a cooperative group novel focused on one significant event or aspect of the war (Antietam, Andersonville Prison, Siege of Vicksburg, etc.) They will be scored for research skills, historical knowledge, narrative writing, writing craft (word choice, voice), conventions, and group cooperation. As an independent alternate project, students are creating multimedia digital narratives focused on any of the focus topics used for the novels. The same learning targets are scored, with the single substitution of technology use for group cooperation. Just about 10% of my students opted for this project, perhaps because they like to play with computer applications, perhaps because they strongly dislike group work. Regardless of their reasons, they are more motivated and more satisfied than if they had been shoehorned into the group project.