摘要:The influence of students’ investment and perception during participation in structured inquiry-based learning on their long-term retention was analyzed to gain more insights into the underlying reasons for long-term retention through structured inquiry learning. Therefore achievement was correlated to effort, lesson rating and perceived competence for learning (PCL), and subject grades. 126 ninth graders participating in a structured inquiry-based interdisciplinary Biology and Physics module were analyzed. Students’ knowledge was even measured four times: 2 weeks before, directly after, and six and 12 weeks after module participation. Effort, usefulness, and PCL were observed once, directly after module participation. The invested effort during the lesson correlated positively with the knowledge score measured six weeks and twelve weeks after the lesson. Thus, high effort individuals achieved high knowledge scores at the medium and the long-term measurement. Therefore, effort is a variable that seems to be linked to long-term achievement. Furthermore, Biology and Physics grades reflected individual abilities to acquire long-term knowledge, while a high preknowledge level did not. This result indicates learning strategies as possible core concept underlying individual achievement levels.