As an educator, having multiple choice questions creates a smooth experience when evaluating student understanding. However, mathematics and STEM related subjects cannot entirely rely on multiple choice questions to evaluate learners. This is because, while getting the right answers is desired, the problem solving process is much more important.
To ensure that learners have mastered the problem solving process, much more advanced tools are needed for evaluation. Such a tool is STACK (System for Teaching and Assessment using a Computer-algebra Kernel), the world leading open-source system for online assessment for math and STEM subjects. It was established in 2005 to help teachers improve maths and STEM assessments.
STACK can be integrated seamlessly with Moodle, ILIAS and other Learning Management Systems.
How does STACK work?
Once integrated to an LMS, STACK allows educators to author questions/mathematical problems that a student needs to provide sequential mathematical answers for using the steps involved in solving the problem. Through this process, STACK establishes its mathematical properties.
The student’s answers can be any mathematical expression, such as an equation, a matrix, or multiple lines of reasoning. Here, STACK ensures a smooth assessment for lecturers and students as it offers;
1. Randomization
STACK uses the Computer Algebra System (CAS) Maxima to generate random structured questions. This ensures that different students see varying questions on the same test, promoting academic integrity and fairness.
For instance;
Dr Samuel, a top Engineering Lecturer, is preparing for an online assessment. He wants to create random algebraic questions to test individual understanding of all the students. To ensure fairness, he uses STACK to generate unique versions of the same question for each student.
2. Immediate Feedback
Student answers get validated before they are graded. Once they type their answers, they see how it is interpreted before it gets submitted, helping them correct any input errors they may have in their answers.
For example;
John, a fourth year student was doing his final online assessment. While keying in the answer, he forgot to put a left bracket in his expression.
Answer: (y+12) y+6)
The system then interpreted his answer highlighting the missing left bracket as follows;
This answer is invalid. You have a missing left bracket ( in the expression (y+12) y+6)
In this case, John fixed his error, and was not penalized for the missing bracket in his initial answer.
3. Answers are graded based on Mathematical Properties
STACK allows subject matter experts to build grading trees to make decisions about the student’s answers.
For instance;
If a quadratic equation is expected to have a root at x=4 but instead has a root at x=-4, STACK might assign partial credit (e.g., 0.60/1.00) and note a penalty (e.g., 0.10) for the discrepancy.
With this, a teacher gives adjusted feedback and marks for the answers provided by students.
4. Graphical Capabilities
STACK supports integration of graphs and plots, enhancing the visual aspects that a teacher would want to include as aspects of mathematical problems including graph interpretation.
Why Use STACK?
Using STACK has various advantages, including:
- Having answers that contain mathematical content
- Establishing the mathematical properties of those answers
- STACK has formative, summative and evaluative feedback for students
- STACK stores data for later analysis
- STACK allows evaluation of the whole working of the student
Conclusion
Using tools like STACK enhances interactive and meaningful online assessments for students particularly in maths and STEM subjects.
At Edutab Africa, we offer learning management system services and help you integrate STACK to improve your E-Assessment practices. Contact us today to discover how STACK can transform your online assessments.