Scholars from the University of Minnesota have addressed the issue of Lab Reports in their article “Development of a Uniform Approach to Writing and Grading of Laboratory Reports in Horticultural Science Courses”, published in the Journal of Curriculum and Teaching. They show that teachers often do a poor job in telling students how to write a lab report and also deviate from official learning outcomes as well as each other in grading lab reports.
The authors have developed a grading rubric based on information from the lecturers themselves, reviewed by curriculum experts. They report that in a trial, students indicated that use of the same rubric in other Horticultural Science courses would demystify the process of conducting research and communicating it effectively in laboratory reports.
This seems relevant to a far wider range of contexts than horticulture in North American universities.