Why it works

There are several aspects of Arc Maths that academic research has shown improve long-term retention of knowledge:

Retrieval Practice

Testing knowledge with questions is the most effective way to remember.
The purpose of the testing is not to assess whether the knowledge is known but to strengthen the memory of that knowledge. A student doing a session of Arc Maths is undertaking retrieval practice and research has shown that this is a powerful tool for improving long-term retention of knowledge and skills.

Spacing Effect

The time between repeat testing increases.
Arc Maths spaces learning out over a period of time, because research shows this is more effective than massed practice in which the same skill is practised repeatedly in one sitting. The increased effort required to retrieve the information after a period of forgetting helps to strengthen the memory.

Interleaving

Topics are mixed-up so you need to decide what maths is needed for each question.
When using Arc Maths, a question on rounding may be followed by one on substitution so students need to identify what maths is required. This is a more demanding task than repeat practice and the greater effort required to retrieve the knowledge or skill has a positive impact on the strength of retention.

Cognitive Load

The interface and wording of questions are designed in a way that minimises any distraction from the learning of maths.
Research has shown that adding unnecessary complexity to a task inhibits learning by overloading the working memory. The questions in Arc Maths are presented with minimal wording and without real-life context where possible. The interface is uncluttered and consistent so that the user can give their full attention to the maths.