This research aims to reveal secondary school students' cognitive and conceptual learning levels in music lessons. In the research, cognitive and conceptual learning competencies in music lessons were discussed in line with students' musical literacy and other musical learning contexts. In this direction, the musical symbol, term, and concept achievement test (MSTCA) were applied to 206 students in a sample group of 12-year-old students from three different schools. The data obtained in the test were categorized and tabulated according to subheadings "duration of the note values, musical expressions, measure indicator." As a result of the research, it was revealed that most students could not conceptualize symbols, terms and concepts especially those related to note duration values. According to the results of the research, it is seen that secondary school students do not understand the musical symbols, terms, and concepts they encounter in the music lesson to a large extent, they have misconceptions, and their learning levels in this field are not at the desired level. Similarly, it is observed that the students need help to fully embody the terms and concepts such as unit beat, tempo, staff, and measure indicator in music. It has been determined that the 6th grade students are not at the level of essential preparedness required for music literacy.