Norway has multiple different grading systems, both unique ones and ones that have been based on foreign grading systems. The formerly most common system of grades used at university level was based on a scale running from 1.0 (best) through 6.0 (worst) with 4.0 or below being considered passing grades.
The way the new Bologna system was introduced implies that students who had started their studies while the old system still was in effect will graduate with transcripts containing grades from both systems (i.e. both numbers and letters).
Lower levels of education use a scale running from 1 through 6, with 6 being the highest and 2 the lowest passing grade. For non-final tests and mid-term evaluations the grades are often postfixed with + or - (except 6+ and 1-) and it is also common to use grades such as 5/6 or 4/3 indicating borderline grades. However, the grades students get on their final paper are either 1, 2, 3, 4, 5 or 6.