Louis,
If you set up the rubric for your lab as a 0-5 scale, with "0" being does not follow directions, does not perform as instructed, fails to keep sterile, fails to follow accepted procedures as outlined, then in incrementals, 1 would be a bit better, 3 would be meets expectations, performs as outlined, does the required work with only 1 major error, etc., 4 would be goes above the requirements, performs at an elevated level of understanding and made only 1-2 minor errors, etc., and 5 being goes above and beyond stated expectations, performs without errors, your rubric would be… >>>