What form might it take? Could problem-based learning work for you? Or a case study? (Here's another) If you are thinking web quest, make sure you know what a real web quest is!
Take a look at some of these examples of online learning and reflect on how they match the criteria for authentic eLearning design. How do they make it happen?
Mysteries of Harris Burdick
Funds for pipeline project
Primary Science Mystery
Please don't underestimate the importance of questions!
Question your design decisions - is it authentic? is it a problem without a simple solution? are ICTs integral and being used purposefully? are students collaborating? etc etc etc
And of course embed questions throughout the learning experiences - why do you think? what if? what are the possibilities?
A couple of great resources for developing those questions:
Bloom's Question Starters
Socratic Questioning

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