Making all or the majority of assessment summative means that students often become preoccupied with obtaining grades rather than on learning. This can lead to strategic or surface learning, or a reduction of the curriculum (Sambell and McDowell, 2006). For example, if you set an essay topic or project at the beginning of the module to complete at the end, students might choose to only attend lectures which are relevant to their essay, therefore reducing the breadth of their learning. If an end-of-term exam is the only module assessment, students might not be motivated to study until the week before.
Too much summative assessment channels students’ attention from assessment to assessment, and away from the parts of the curriculum which are not assessed. Too little means less meaningful learning occurring throughout course, and there are few opportunities to practice assignments and to obtain feedback (Jessop et al, 2014).
Formative assessments affect (and can transform) learning, but they don’t impact on a students’ degree transcript, so are not usually subject to the same college regulations and scrutiny as summative assessments. Therefore, there is more freedom for teachers to innovate and for students to take the risks that are required for meaningful higher education (see King’s Academy’s webpages for the Excellence in Teaching conference on Risk in HE). Key factors such as feedback and indicators of performance still need to be considered, but the usual reliability concerns are less significant and therefore, learning, rather than equitable measurement, can be a primary concern.