The main difficultly with prompt design now is that there are so many student "help" and cheat sites on the internet that it is very difficult to create assignments that students actually do themselves. Your best choice might be a survey or thick description assignment where students have forms that they need to fill out by direct observation. For example, they could do an opinion survey of what other students considered the five leading cliques in their school. Then they could discuss that clique structure in terms of various markers such as income, cultural capital, ethnicity, religion, etc.
What natural constructs in your personal life are socially constructed?
What creates a contentious relationship between people? Provide a specific anecdotal example.