Today´s youth are making extensive use of technological devices such as smart phones and computers. These devices are based on inter-disciplinary knowledge. Are these young students attracted to learn the computer principles that these devices are based on? Many educators agree that one of the methods to foster learning in school is to connect the topics of study with students´ interests, experiences and daily life, ‘contextual learning´. This paper describes a research aimed at examining the case of teaching a course on computer image processing to middle school students, and evaluating its influence on students cognitively and effectively. The study included the development, implementation and evaluation of a computer image-processing course. The course was taught to 34 9th-grade students in two groups. The control population comprised 64 9th-grade students in three groups. The study included developing an instructional model consisting of four phases: teaching theory, manual and computerized practices, implementing challenging tasks, and projects. Data were collected by using quantitative and qualitative research tools, such as two exams, three projects and a half-opened attitude questionnaire about learning computers, class observations and semi-structured interviews with students and teachers. Findings showed that young students´ achievements were very well in learning principles of image processing. In the mathematics exam, the experimental students´ achievements were significantly higher than the control students´ achievements. The students showed high motivation and great interest in learning the course. Finding showed that the instructional model developed in the study was the main component influencing the experimental students´ achievements and motivation.