The following article will show you how to delete a benchmark from your tracker.
If you don't see the Delete option, it means that your administrator opted not to allow teachers to delete it. If so, you will have to contact your administrator for further help.
Delete Benchmark and Confirm
Click on Trackers, and select the tracker from which you want to delete the benchmark.
Hover over the benchmark title and select Delete.
Click OK on the warning window. Remember that deleting a benchmark will also permanently delete any scores associated with it.