The geography subject in Swedish upper secondary school is in a marginalized position with just two national programs having it as a mandatory subject. No mention of the skill of spatial thinking is made in the regulation documents from the Swedish National Agency for Education. To investigate the spatial thinking in the Swedish upper secondary school, I constructed a test that 140 students conducted. From the results it was possible to deduct that the students performed well in areas of spatial thinking that deals with geographical features like points, lines and polygons, but not so well when faced with tasks concerning several spatial facts, overlay, and mentally visualizing 3-D images from 2-D information. Males generally scored higher than females in the test, especially if only answers that the students felt confident of were counted. Students from the Natural Science Programme outperformed the students from the Social Science Programme, even though the former didn’t have any formal education in geography from the upper secondary school. The thesis argues that a larger focus on spatial thinking in the geography subject could benefit the development of both a stronger stance for the subject in the education system, and the abilities and knowledge tied to spatial thinking of the students, especially those that are lacking formal education in other subjects that train the spatial thinking, mostly mathematics and physics.

As climate changes are progressing so is the need for further knowledge surrounding them and their consequences. This includes the ocean’s role in the climate system. Previous studies indicate a general lack of research in students’ understanding of the ocean, which this thesis aims to fill a part of. This thesis has investigated upper secondary school students’ basic knowledges of the ocean’s natural processes and chemistry, as well as the students’ understanding of the consequences of the ongoing ocean warming. The methods used have been a combination of participant observation and a quiz, considering students in an upper secondary school in Stockholm. The results of the quiz show that two thirds of the students have a basic understanding of the ocean’s processes and chemistry. The participant observation supports this conclusion. It additionally showed that most students displayed superficial knowledge of oceanic processes, while having a poorer understanding of more complex processes and the concurrence between processes. Some misunderstandings and alternative understandings surfaced amongst the students’ answers. These, along with systematic geography and its preconditions, are discussed in the discussion section. While the present study was too limited to draw definite conclusions, this study indicated preliminary that students with focus on natural science display a deeper knowledge in the ocean’s chemistry and natural processes than students with focus on social sciences, which would be interesting to investigate further in future research.