Tasks used for assessment can range from short pithy questions to focus on a concept, such as "What is a sample?" or "What is variation?", to multi-part tasks that build in difficulty to discover students’ optimal level of performance (e.g. Comparing Two Groups).
It is important to consider the marking scheme while a task is developed and this is likely to be associated with an assessment rubric.
A bank of survey or test items suitable for middle school is found in appendix C (page 31) to the paper on Statistical Literacy (286 KB PDF from the International Association for Statistical Education website). You can also use the covariation assessment to determine students' prior learning.
Many brief tasks, often multiple-choice or computationally based, are available in textbooks or through the Australian NAPLAN website.
This multi-part task gives students the opportunity to suggest a method of surveying a school, as well as comment on surveys conducted by others.
Prediction from a pictograph
This multi-part task is based on a pictograph. It requires students to draw on their understanding of the context to explain and justify their predictions.
Critical thinking about average
This multiple choice task about the mean can be used as either a test item or as an extended task.
Graph reading and scale
This task focuses on reading two simple stacked dot plots and considering the issue of scale.
Comparing two groups
This task is usually the basis for an interview with individual students to gauge their ability to consider the features important in comparing two data sets. This ability is a prerequisite for informal inference when the data sets are samples from two populations.
Assessing the media
This assessment task asks students to think critically about the media and presents them with a pie graph where the percentages do not sum to 100%.