You can group your staff in teams to match your org. structure.

To define who belongs to a team leader (manager, coordinator, team lead,...).
Go to the screen of the team leader(a person) and add the module: Team

When a team is setup, the team leader will see only her team information, in:

1. Approval
   Team leaders are able to view, approve or reject the timesheets of their team only.
   Team leaders are not able to approve their own timesheets.
   
   
2. Reports
   Only the data of the team leader and team members will be available in the reports.

The Team Leader users, with Team left empty, will have access to everyone in the Approval  module
And will see all hours done by company employees in Report

The administrators have also full access on both Approval and Report