Purpose: The purpose of this paper is to report on the rationale behind the use of a unique paper-based individualised accounting assignment, which automated the provision to students of immediate formative and timely summative feedback. Design/methodology/approach: As students worked towards completing their assignment, the package provided immediate formative feedback with sufficient indicators for the student to identify that they had made an error and provided encouragement for the student to take appropriate corrective action until they were satisfied that their answer was correct. Once the student was satisfied with their work, their submission was automatically marked by the assessment package according to the pre-set marking scheme. Findings: The assignment experience reported here has shown the potential for interactive spreadsheets to be created for a wide range of rule-based accounting problems to provide formative and summative feedback. The package can be (and has been) easily extended beyond financial accounting to many other accounting- and non-accounting-related fields, e.g. tax, audit, economics and statistics. In fact, individualised assignments utilising interactive spreadsheets appear to have broad applicability in any educational context (including mathematics, engineering and science) where a correct numerical answer is required. Originality/value: The unique automated feedback and marking package was developed by the author utilising Microsoft's Excel spreadsheeting tool. The marking package generated a detailed summary providing important feedback to students clearly identifying correct answers and specific problem areas, enabling the student to review these aspects. The package also provided feedback to the teacher identifying the cohort's performance on each item in the assessment. (Contains 1 figure and 1 table.)