Every Monday and Wednesday, while we wait for my wife's lecture to start, we listen to a group of soil science undergraduates discussing their weekly assignments. A couple of the students know what they're doing but more seem confused. What they're confused about is the mathematics. The maths is quite simple, from my perspective, they are simply calculating masses for the most part. At any rate all of the calculations only involve multiplication, division, addiction or subtraction.
There are two reasons why these undergraduates seem confused. The first is that find themselves baffled by mathematics in general. You have to wonder why such students chose to study a science for their degree. This same problem happens back in the UK. Students who are interested in science but dislike mathematics choose what are perceived to be softer sciences, such as environmental science, thinking they can minimise the amount of calculations they'd have to perform. Unfortunately for these students soil science and other such disciplines contain a lot of calculation. There is a perception problem. The perception is that the earth and environmental sciences contain a lot more descriptive analysis than quantitative.
The second reason that these students are baffled is that they have to use metric, a system that they are not used to. When you grow up knowing about feet and inches, it is hard to envision centimetres and metres. Making it harder for the students is that the initial questions are set in Imperial units. That's to say the students have to convert from Imperial to Metric in the course of their answers. The questions are set in Imperial because it helps the students to visualise the problem. However, their answers are required to be in SI units (which are mainly metric) because they are studying a science. This leads to some statements along the lines of "What do we multiply by to convert from yards to metres?"and "Do I have to divide by 14 here". This leads me to think why make it so hard for them. Why not just use metric measurements in the first place.