INDIVIDUAL INSTRUCTION IS RECOGNIZED AS AN EFFECTIVE LEARNING METHOD WHICH IS HIGHLY SUPPORTED BY THE SO-CALLED PERSONALIZED, INTELLIGENT OR ADAPTIVE SYSTEMS. THE MAIN PURPOSE OF THIS LEARNING METHOD IS TO OFFER CUSTOMIZED CONTENT, EXPERIENCE OR TOOLS, BASED ON THE LEARNING PROFILE OF STUDENTS (LEARNING STYLE, GENDER, PRIOR KNOWLEDGE, LEARNING GOALS AND SO ON), SO AS TO IMPROVE THE LEARNING OUTCOMES. THERE ARE TWO WIDE-KNOWN ADAPTION TECHNIQUES IMPLEMENTED BY LEARNING SYSTEMS TO PROVIDE INDIVIDUAL INSTRUCTION: ADAPTABILITY AND ADAPTIVITY. THE FIRST ONE ALLOWS THE STUDENTS TO TAKE CONTROL, E.G. THE LEARNING SYSTEM PROVIDES CHOICES TO LET THE STUDENTS ADAPT THE STEPS, SEQUENCES, DIFFICULTY LEVEL, PREFERENCES, WHILE THE SECOND EMPOWERS THE SYSTEM, WHICH IS ABLE TO BUILD A STUDENT MODEL AND TO PROVIDE LEARNING SUPPORT BASED ON THAT MODEL. THE CURRENT PAPER PRESENTS POLICAT - A LEARNING SYSTEM BASED ON COMPUTER ADAPTIVE TESTING (CAT) PRINCIPLE, WHICH IMPLEMENTS THE SECOND ADAPTION TECHNIQUE (ADAPTIVITY) TO PROVIDE INDIVIDUAL INSTRUCTION. FURTHERMORE, THE PROPOSED WEB BASED APPLICATION SUPPORTS THE NEW LEARNING PARADIGMS, E.G. STUDENT-CENTERED LEARNING, COMMUNITIES OF PRACTICE, AND CONSTRUCTIVISM IN GENERAL AND RELIES ON THE CURRENT TECHNOLOGIES - WEB 2.0 AND SOCIAL WEB, AS STUDENTS ARE ABLE TO SHARE ONE'S RESULTS ON SOCIAL MEDIA. THE SYSTEM IS DESCRIBED AS A USEFUL TOOL FOR SELF-REGULATED LEARNING, ANSWERING THUS AT THE QUESTION WHETHER ASSESSMENT MAY HAVE A STRONG FORMATIVE ROLE IN LEARNING OR NOT. BESIDES HIGHLIGHTING THE KEY FEATURES OF THE APPLICATION, THE PAPER PROVIDES EXPERIMENTAL RESULTS FROM A WEB PROGRAMMING COURSE FOR FORTH YEAR STUDENTS ENROLLED IN AN ENGINEERING DEGREE PROGRAM, WHO USED THE DEVELOPED SYSTEM AS A LEARNING TOOL DURING ONE SEMESTER. STUDENTS REPORTED THAT THEY SUCCEEDED IN STRENGTHENING THEIR STUDY SKILLS AND MONITORING THEIR ACADEMIC PROGRESS THROUGH THE LEARNING ANALYTICS FEATURES. THE AVAILABLE PERSONALIZED FEEDBACK POLICAT, AS WELL AS THE POSSIBILITY TO SHARE ONE'S RESULTS IN AN E-COMMUNITY MAKES THE INSTRUMENT TO BE AN ATTRACTIVE TOOL FOR TODAY'S SOCIAL AND CULTURAL VALUES OF STUDENTS, FACT PROVEN BY THE EXPERIMENT AS WELL.