MCAS MCAS information. Student MCAS Sign In Turn on the student's Chromebook and wait for the login screen to load. DO NOT SIGN INTO THE CHROMEBOOK! On the bottom left, select ' Apps' . Then select ' TestNav' . Wait for TestNav to load. The first time TestNav loads it will ask what state you are in. Students seem to have trouble with this step and will select the wrong state. We are in Massachusetts . You will be brought to the sign in page. Students must use the username and password from their test ticket . Note that it says Massachusetts above the 'Sign In' box. If there's a different state or ACT listed, open the menu on the top right, click the down arrow next to the person icon, then click ' Choose a different customer' . Make sure you select Massachusetts. You will then return to the sign in screen and the student can login using the information from the test ticket.