Knowledge and skills are context-bound and therefore difficult to transfer to another context. Research shows that retrieving information from long-term memory is influenced by the context in which the student is situated. When learning, we create context-bound schemas of knowledge and skills in our long-term memory. These schemas are activated when we need to undertake something within that same context. Context includes all characteristics of an explanation, test, or item. If the circumstances change, the knowledge and skills remain (partially) behind: they are therefore harder to retrieve in a different context. This means that a student can solve a particular formula well in Mathematics but struggles with the same formula in Physics. The more complex something is, the harder the transfer. Students need support in transferring that knowledge and skills. This can be done, for example, by making the similarities between different subjects and skills clear to them by making the information rich in context. It can also be done by deliberately practicing applying knowledge and skills. This way, students break free from the context of the learned material. For example, let the students think about in which situations the knowledge/skill might be useful.
Smith, S. M., Glenberg, A., & Bjork, R. A. (1978). Environmental context and human memory. In Memory & Cognition, 6(4), 342-35. https://doi.org/10.3758/BF03197465
Christodoulou, D. (2017). Making Good Progress? Oxford: OUP