Why Indian Students Lose Science Fairs

School science fairs remain among the most visible STEM assessment events in the CBSE and ICSE academic calendar, yet most students approach preparation with limited guidance on what judges actually evaluate. This paper analyses 300 science fair entries across 50 schools in Maharashtra, examining the correlation between preparation quality, project kit type, and judge evaluation scores. Analysis reveals that the top three causes of poor scores are: inadequate working model functionality (46%), inability to explain the underlying science (38%), and poor presentation quality (16%). Students using quality ready-made kits with tutorial support scored 22% higher on average and were 3x more likely to qualify for district-level competition. Practical preparation guidelines are provided for students, parents, and science teachers.