An Approach to Measuring the Difficulty of Learning Activities

In any learning environment, training activities are the basis for learning. Students need to practice to develop new skills and improve previously acquired abilities. Each student has specific needs based on their previous knowledge and personal skills. The allocation of a proper activity for a particular student consists in selecting a training activity that fits the skills and knowledge of the student. This allocation is particularly important since students who are assigned a too hard training activity will tend to leave it rather than making the necessary effort to complete it. Moreover, when the activity is too easy it does not represent a challenge for the student and the learning outcomes will tend to be very limited. An motivating activity, suitable for a given student, should be neither too easy nor too difficult. The problem arises when trying to measure or estimate the difficulty given any training activity. Our proposal is a definition of difficulty of a learning activity that can be used to measure the learning cost of a general learner. As a first step, the desirable features and the intrinsic limitations of a difficulty function are identified, so that a mathematical definition can be obtained quite straightforward. The result is an intuitive, understandable and objectively measurable way to determine the difficulty of a learning activity.