clone rubric added (#455)

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->
## Summary by CodeRabbit

* **Documentation**
  * Expanded Grade Book grading instructions with step-by-step workflows
* Added two explicit grading methods (assignment view and overview) with
procedural guidance
* New section describing how to clone and attach rubrics, noting copies
append to existing items
* Clarified point allocation, rubric deductions, and optional points
adjustment
* Updated and added images to illustrate rubric and grading steps, with
adjusted image sizing

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settings.</sub>
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Author: LolaValente

source/img/guides/Gradebookgradingscreen.png

@@ -31,13 +31,81 @@ A Grade Book assessment may be used to manually grade assignments, it will not a
 Grading a Grade Book Assessment
 -------------------------------
 
-The instructor must :ref:`open a student assignment <viewing-student-work>` to complete the Grade Book grading. Locate the Grade Book assessment in the student file and click **Grade**.
+
+.. note::
+   When grading, click on the 0 or 1 to allocate initial points for overall correctness, then use the other rubric items to subtract points for missing items. There is also a **Points adjust** field if you wish to adjust total points upwards.
+
+
+Instructors can grade Grade Book assessments using either of the following methods:
+
+**Method 1: Grade from the Student Assignment**
+
+1. :ref:`Open the student assignment <viewing-student-work>`
+2. Locate the Grade Book assessment in the student file
 
 .. image:: /img/guides/assessment_gb_opengb.png
    :alt: Grade book assessment
 
-Click on the 0 or 1 to allocate initial points for overall correctness and then use the other rubric items to subtract points for missing items. There is also a **Points adjust** field if you wish to adjust total points upwards.
+3. Click **Grade**
 
 .. image:: /img/guides/assessment_gb_grade.png
-   :alt: Grade book assessment
-   :width: 700px
+   :alt: Grade book assessment grade
+   :width: 500px
+
+**Method 2: Grade from the Assignment Overview**
+
+1. Go to the assignment overview
+2. Click the points corresponding to the student you want to grade
+
+.. image:: /img/guides/assignmentOverview.png
+   :alt: Assignment Overview Grading
+
+3. Click the Grade Book assessment
+
+.. image:: /img/guides/Gradebooktesticon.png
+   :alt: Gradebook test icon
+
+.. image:: /img/guides/Gradebookgradingscreen.png
+   :alt: Gradebook grading screen
+   :width: 450px
+
+
+
+Cloning a Rubric for a Grade Book Assessment
+--------------------------------------------
+
+You can clone a rubric for a Grade Book assessment using either of the following methods:
+
+.. note::
+   If you already have rubric items in the Grade Book assessment, copying another rubric will append the new rubric items to your current rubric rather than replacing them.
+
+**Method 1: Clone from Content Editing**
+
+1. While creating a Grade Book assessment, navigate to the **Grading** tab
+2. Click the settings gear icon next to **Rubric Items**
+
+.. image:: /img/guides/gradebookgearicon.png
+   :alt: Rubric settings gear
+   :width: 450px
+
+3. In the pop-up window, click the rubric you want to copy
+4. Confirm your changes by clicking **yes**
+
+**Method 2: Clone from Assignment Overview**
+
+1. Follow steps 1-3 from **Method 2: Grade from the Assignment Overview** above to open the Grade Book assessment
+
+2. Next to **Total Points**, click **Copy Rubrics**
+
+.. image:: /img/guides/gradingwindowcopyrubricbutton.png
+   :alt: Copy rubric button
+   :width: 450px
+
+3. Click the arrow next to the rubric you want to copy
+
+.. image:: /img/guides/copyrubricarrow.png
+   :alt: Rubric list
+   :width: 450px
+
+4. Confirm your changes by clicking **yes**
+