1. A Web-based Automatic Program Grader
Don Colton, Leslie Fife, Andrew Thompson
School of Computing
Brigham Young University Hawaii

2. Order of Presentation Motivation/Rationale GradeBot Discussion
WebBot Improvements
Observed Results
Conclusions/Future Work

3. Motivation/Rationale
Ability to program – critical tool
Pace of assignments difficult for beginning students
Beginners need more and smaller steps
Beginners need rapid feedback
Grading Burden Introduced
Large Classes
More assignments with fast feedback
Perfect Programs Paradigm

4. GradeBot Grading Model Infinite Loops Handled Core Dumps Eliminated
Submit programs in any supported language
Automated Test Case Creation
Comparison to expected output
Expected results (with test case) returned for debugging
Infinite Loops Handled
Core Dumps Eliminated
New Lab Creation Simplified

5. WebBot Adds a User Interface to GradeBot
Simplify the Editing/Submission Process to decrease startup time for new students.
Postpone the challenge of learning new tools (Emacs, IDEs, etc.)

6. WebBot Login

7. WebBot Workspace (frames)

8. WebBot Status Report

9. WebBot Options Page

10. WebBot Discussion
IDE Introduction
not prevented
only delayed
Cheating

11. Table I: WebBot Submission History
Observed Results
Table I: WebBot Submission History
Year
2004
2005
Course
CS 1
CS 2
Algorithm
Analysis
Students
175
133 19
169
117 42
Submits
(purged)
73405
15043
5684
Success
6995
1007
189
6518
767
385
Success %
8.9%
5.1%
6.8%

12. Conclusions/Future Work
Does Not Handle
Style not graded
Cannot provide detailed help in all cases
Does Handle
Large number of Requests
Perfect Programming Paradigm
Open Entry/Open Exit
Next: Instructor Interface Module

13. Mahalo!