Last year, my colleagues Grace Gurman-Chan and Rachelle Grossman and I led an online workshop on 'Engaging children in the Passover seder.'
You can access the entire workshop (audio recording, and all the materials) at
http://bit.ly/sederideasforkids. It includes a review of the history of the Passover seder, focusing on how at its origins its structure was much more flexible than many people imagine today, as well as all kinds of suggestions and links to great Seder resources. This may be a valuable resource for you at this time of year!