The importance of mathematical reasoning is unquestioned and providing opportunities for students to become involved in mathematical reasoning is paramount. The open-ended tasks presented incorporate mathematical content explored through the contexts of problem solving and reasoning. This article presents a number of simple tasks that may be suitable for stimulating students' mathematical reasoning. While each task is presented as a possible context in which mathematical reasoning can be applied, solutions may also be obtained by non-mathematical means. This allows all students to be engaged, although the teacher may wish to guide discussion towards the salient mathematical aspect(s) of the task. The open-ended nature of the tasks also allows various levels of mathematical reasoning to be applied.