This paper investigates tutoring feedback strategies adaptive to student motivation. Several static feedback adaptation strategies have been designed based on the interactive tutoring feedback (ITF) model, implemented within the Adaptive Educational System (AES) ActiveMath and evaluated in a study with 6th and 7th graders. Student motivation profile (high vs. low perceived competence and intrinsic motivation) has been used to assign them to either conceptual or procedural feedback condition. The data analysis shows that, for low motivated students, the benefits of adapting feedback to motivational profiles are visible in both, performance during treatment and knowledge gain from pre- to post-test. For highly motivated students, no significant effects have been registered. These findings shed light on the role of motivation in tutoring feedback processing and have important methodological implications for designing feedback strategies in AESs.