Digital Examination with Molecular Structural Formula Editor (MOSFECCS)
At the end of each semester, more than 400 students take the session examinations for the courses Organic Chemistry I and II. These examinations have been conducted digitally on ETH computers since 2018. A key highlight is the Molecular Structural Formula Editor (MOSFECCS, 'Molecular Structural Formula Editor and Calculator of Canonical SMILES'), a tool that allows students to draw molecules directly on the computer and then encode their structures as alphanumeric strings (so-called SMILES codes, 'Simplified Molecular Input Line Entry System').
Examination tasks are provided via Moodle, students develop their answers partly in MOSFECCS and then submit them in Moodle as SMILES strings. The Moodle question type Embedded Answers (Cloze) simplifies the work of examiners by enabling automated correction of these alphanumeric strings, ensuring efficient and transparent grading.
Examination tasks are provided via Moodle, students develop their answers partly in MOSFECCS and then submit them in Moodle as SMILES strings. The Moodle question type Embedded Answers (Cloze) simplifies the work of examiners by enabling automated correction of these alphanumeric strings, ensuring efficient and transparent grading.
All Course Assessments
Overview of the Course
What is the subject context of the course?
The two courses cover structural aspects of organic molecules (Organic Chemistry I, OC I) and their reactivity, as illustrated by fundamental organic chemical reactions (Organic Chemistry II, OC II)
What should students learn and be able to do at the end of the course?
OC I:
The main learning objectives are to understand the electronic structure of molecules, their chemical bonds, and their three-dimensional structure (stereochemistry). A major section is further dedicated to the various spatial arrangements resulting from rotation around single bonds and the associated energies (conformational analysis). Students should be able to graphically represent three-dimensional molecular structures using appropriate formulae.
OC II:
The focus of this course is on the relationship between molecular structure and reactivity. This is accomplished by studying a number of fundamental reactions of organic chemistry and their step-by-step mechanisms. At the end, students should be able to predict the outcome of a reaction or suggest one- or two-step syntheses for relatively simple target molecules.
Why was the specific assessment format chosen?
For nearly two decades, we have used Moodle as the learning platform for these courses. The goal was to allow students with different educational backgrounds to practice independently according to their needs. The Moodle course was well received and ultimately led to the idea of a digital exam. I also hoped that digital exams would simplify the grading process, especially since approximately 400 students are participating.
How are students prepared for the assessment?
There is a multi-stage preparation:
1. At the beginning of the first semester, a Moodle quiz is offered as a way of assessing the current proficiency in the subject. This helps students to identify gaps in their knowledge so that they can address them systematically. The students’ educational backgrounds (high schools) and interests (study programmes) are very diverse.
2. The Molecular Structural Formula Editor MOSFECCS is introduced during a tutorial in the 3rd/4th week of first semester. Students can use it throughout the year within the Moodle course. As a consequence, they rarely ask technical questions during the exam.
3. There is a classic tutorial with student coaches for in-depth reflection and discussion of the course material (OC I from the 3rd week until the end of the semester / OC II throughout the semester).
4. Quizzes are provided in the Moodle course after each chapter. Taking them is optional but recommended.
5. There are two self-assessments in Moodle: one in the middle of the semester and one at the end. They have easier questions than the exam because students are not expected to prepare for them specifically. Taking the self-assessments is optional but recommended.
6. There are many old exams available on the Moodle course. They are a popular resource for exam preparation.
Course Fact Sheet
OC II: 5
HS24: 529-1011-00L Organic Chemistry I
FS25: 529-1012-00L Organic Chemistry II
D-HEST: Health Sciences and Technology Bachelor, First Year Examination, Compulsory
D-CHAB: Pharmaceutical Sciences Bachelor, First Year Examination Block 2, Compulsory
Competencies Fact Sheet
Concepts and Theories (assessed)
Analytical Competencies (assessed)
Communication (fostered)
Sensitivity to Diversity (fostered)
Creative Thinking (fostered)
Critical Thinking (fostered)
Integrity and Work Ethics (fostered)
Self-awareness and Self-reflection (fostered)
Self-direction and Self-management (fostered)
Assessment Fact Sheet
(Feasible for 25 - 800)
OC II: 75 minutes
Both examinations (OC I and OC II) are offered after each semester.
The reason for the feasibility for 25 – 800 candidates:
- This digital examination requires more preparation than a paper examination. With fewer than 25 candidates, the cost-benefit ratio of a digital exam is no longer favourable.
- The examination would be feasible for up to 800 candidates. However, if the examination has to be conducted in different ETH buildings, the coordination effort increases significantly.
Resources
ETH computer room
(ONA building in Oerlikon, with 400 examination places at ETH Computers (as of HS24))
Moodle
The following Moodle question types are used:
- Embedded Answers (Cloze) for multiple choice and short answer
- Drag and Drop into text
- Kprime (ETH)
- MTF (ETH)
- Ordering
There are 45 questions for both parts of the exam, OC I and OC II.
Safe Exam Browser
- Structural Molecular Formula Editor MOSFECCS
(JavaScript [ECMA script5.1] using Canvas elements as defined in HTML5) - Digital calculator
OC II: Overview of chemical reaction pathways (digital and on paper)
Grading and Feedback
Lecturer
Staff Workload (400 Candidates)
| Time | Staff | |
|---|---|---|
| Exam Preparation | 3 Working Days | 1 Lecturer |
| Exam Process | 5 Hours | 1 Lecturer and 10 - 15 Student Teaching Assistants |
| Grading | 5 Working Days | 1 Lecturer |
Exam Preparation
Exam Process
Grading
Extra Information
- Exam Preparation
The preparation for the examination questions is made throughout the semester. It takes the equivalent of 3 working days to create the questions and set up the examination in Moodle. - Exam Process
The lecturer and 10 – 15 student teaching assistants are needed for the monitoring of the examination. - Grading
The grading process is undertaken by the lecturer and takes 5 days.
Shared Experience
How many times has the assessment been conducted in this format?
In 14 sessions over 7 years.
What contributed to the success?
- The examination process is well-established at all levels and runs smoothly without significant issues.
- Although setting up digital exams is more demanding and time-consuming, it is also more interesting than creating paper-based exams. With a class of several hundred students, the main drawback of paper-based exams is the repetitive and time-consuming grading process. Overall, the effort required is similar in both cases, especially since I do not only ask multiple-choice or true/false questions, which are automatically graded.
- I also appreciate how well the exam aligns with the learning activities in the Moodle course.
What were the challenges and how were they overcome?
- For the first few exams, we corrected unexpected but partially correct answers directly in Moodle (many answers involving molecular structures fall into this category). With several hundred candidates, this process is technically extremely tedious and time-consuming due to the countless clicks and long loading times for Moodle pages. We were only able to process the data more efficiently and streamline the assessment process by writing our own scripts to work on the data exported from Moodle. Currently, we mark partially correct answers in Excel spreadsheets and import the scores into Moodle. An additional advantage of this method is that identical answers always lead to the same score for all candidates.
- Thanks to a close collaboration with Prof. em. B. Jaun, the MOSFECCS editor was continuously optimized, and we resolved a few minor technical issues that arose initially.
Are there any further developments planned?
There are no concrete plans at present, but I have a few ideas.
Currently, evaluating large quantities of test responses in Moodle is very cumbersome (see previous point). Ideally, the functionality of this procedure would be expanded and improved to make it efficient and streamlined as possible. This would eliminate the need for self-written scripts to process the data, which sometimes require adaptation when Moodle has been updated.
It would also be nice to have a «chemical» Moodle question type with an integrated editor for molecular structural formulae. Such a question type had been created in the Moodle community a number of years ago, but unfortunately, its development was discontinued.
What tips would you give lecturers who are planning a similar assessment?
MOSFECCS is publicly and freely available on Github (see link at the bottom of this page). Integrating it into Moodle is a cinch. I am happy to act as a point of contact and provide a demonstration, if desired.
Shared Materials
With these student numbers, I'm glad that the team Digital Examinations is there as technical support in the background.