Abstract:

This paper describes an innovative learning experience that has been performed in a course of Digital Signal Processing for five consecutive years. This course of Digital Signal Processing is an obligatory subject of the 4th year of Telecommunication Engineering at the Escuela Politecnica Superior of the Universidad Autónoma de Madrid. Briefly stated, the experience consists in conducting an auto-evaluation test at the end of each theme of the course. This, by itself, is not really very innovative. The innovative part of the experience relies in how the test is produced, the byproducts it generates and how it is taken by the students and taken into account for evaluation.

First, the students are involved in preparing the test in the following way. After the theory of a theme is presented the professor asks for two voluntary groups of three to four students for preparing a total of 32 test questions (16 each group) with 5 possible answers each. These questions are sent separately to the professor, who makes comments and corrects some of the questions and answers, and selects 20 out of the 32 (usually 10 from those of each group) for the final auto-evaluation test.

This test, with 20 questions, is passed to all the students at the end of a theory class for about 20 minutes, ideally during the next theme. The students are warned in advance about the date of the test so that they can study in advance if they wish, but they are also warned that the auto-evaluation tests are just AUTO-evaluation (i.e. the score achieved is never known by the professor and therefore not taken into account for the final evaluation). It is very important to make very clear this point because otherwise the students in the group would probably pass the questions and answers to the rest of the class, making the whole experience useless.

After the students have corrected and evaluated their tests individually, they are asked to discuss the questions that they have found more difficult with other students in groups, and after that discussion the students are asked to share their questions with the rest of the class and the professor. This discussion is very fruitful and sometimes clarifies wrong concepts.

At the end of the discussion the professor asks students to raise their hands if their score is in some ranks (usually over 10 and over 14 in a scale between 0 and 20). This provides important feedback to the professor about the level of understanding of each theme, without the pressure on the students of a theme-by-theme evaluation.

Finally, the test along with its solution, and also the 32 questions generated by the two groups with solutions, comments and corrections from the professor are published on the web page of the course, which provides feedback to the students that have prepared the test questions, as well as additional material for study to the students. Since the course comprises 6 themes, the final result is a total of 32x6 = 192 questions with their answers, all of them commented and corrected by the professor. The students find this material very useful for practicing for the real evaluation.

The paper explains in detail this experience and correlates it with results in subjective opinion of the students and with objective evaluation results.

Keywords:

Collaborative learning, assessment of student learning, auto-evaluation.