As an instructor, you may be able to limit the number of submission attempts allotted to students for an assignment. Limiting assignment attempts is only available for assignments with the Online submission type.
To open an existing assignment, click the assignment name .
To create a new assignment, click the Add Assignment button .
Select Submission Attempts
Locate the Submission Type setting  and select the Online option . Then locate the Submission Attempts setting .
Set Number of Attempts
By default, the Allowed Attempts setting is set to the Unlimited option . If this option is selected, students will be able to resubmit the assignment as many times as necessary.
To limit the number of attempts allowed to students, select the Limited option . Then select the number of attempts in the Number of Attempts field .