What inferences can you make for 34kg about 136 pounds is the mass of a middle school student?

The inference we can make from the statement "34kg (about 136 pounds) is the mass of a middle school student" is that this student is likely overweight or obese for their age and height.

While 136 pounds isn't automatically unhealthy, it's significantly higher than the average weight for a middle school student. To determine if this weight is truly problematic, we would need additional information, specifically the student's height and age. Body Mass Index (BMI) calculations require both height and weight to accurately assess health. Without that, we can only infer a possibility of excess weight.