[Documentation:InstructorUI] Remove Print Lab

_docs/grader/checkpoint_grading.md

@@ -4,13 +4,14 @@ title: Checkpoint Grading
 ---
 
 The *Checkpoint Grading* interface is appropriate for simple,
-low-precision grading -- for example for attendance of completion of
-laboratory modules.
+low-precision grading -- for example to track attendance or completion of
+laboratory modules. In addition to checkpoints, text fields
+can also be added to these gradeables.
 
 ![](/images/ta_grading/TA_lab_grades.png)
 
-The TA clicks once to give the student full credit (dark blue), or the
-TA clicks twice to give the student half credit (light blue).  A
+The TA clicks once on a checkpoint to give the student full credit (dark blue), or the
+TA clicks twice to give the student half credit (light blue). A
 triple click returns the box to zero credit (white).
 
 Instructors and Full Access Graders can view the timestamp and grader