Think of your progress weeks as sprints. You could do 2 one-week sprints or 1 two-week sprints at the start, and one-week sprints for your final term.
Make a list of tasks to do in the sprint. These should be scrum-like. Think of user stories. Make them small enough, actionable enough that you can accomplish them. If they are broader, that may be ok, but provide sub-tasks for each so each is actionable (i.e., you have a concrete, if brief, description of what it includes, like a homework assignment). Do this as a group! Everyone should brainstorm and contribute to this list, even if one person is writing/organizing taking notes while you do this in real time. Consider organizing this list in Trello or something similar.
Put a name by each of the tasks/sub-tasks in the list. Everyone must volunteer themselves for this list. No one is going to assign you to items on the list. This is part of the "step-up" attitude. Make sure to have names next to everything on the list. Some items probably should have two+ names next to them, where people work as a pair (especially when there are sub-items).
Work on the items with your name on them. That's not to say there are still not other items to help with. You are a team and you might need to help with other tasks. You definitely need to communicate progress and blockers.
Meet frequently. Scrum-like, where you talk about: what you did since last time, what you are doing next, any blockers. This can be a short meeting - it is status and not meant for longer discussions. If there are blockers, you schedule additional meetings with some/all of the people.
At the end of the sprint, have a retrospective. Discuss: 1) what went well, and that you'd like to continue, 2) what didn't go well and that you'd like to improve. Do this as a group. produce a short list/document for this. Consider sharing this with your advisor/mentor.
Plan the next sprint based on the user story backlog. This will include any unmet items on the previous sprint (you probably want to visit why the didn't get done in the retrospective).