Final answer:
The most likely instructional practice leading to a decline in academic interest during early adolescence is an increase in whole-group lectures. This method could reduce engagement and contribute to grade inflation, affecting motivation. Adjusting instructional practices and school incentives may help to mitigate these issues.
Step-by-step explanation:
The decline of academic interest and motivation during early adolescence may be attributed to multiple factors, including instructional practices. One such practice that is identified as a probable culprit for the decline in motivation is an increase in whole-group lectures in middle and junior high schools. This increase can lead to a more passive learning environment, which may negatively impact student engagement compared to the more interactive and varied instruction often found in elementary schools. Furthermore, this change coincides with evidence of grade inflation, where the standards for academic achievements are perceived to be lowered over time, potentially undermining motivation for high-achieving students. Research suggests that various measures, such as altering incentives for schools and adjusting instructional practices, could address these issues. Particular initiatives might include testing students regularly, providing teacher rewards based on performance, and empowering students with more decision-making opportunities.