I have timed the presentation, it will go anywhere from 30 to 40 minutes, depending on how much participation I get from the kids. I actually do have a pretty animated personality and plan to ham it up and keep the kids engaged, rather than lecture them.

I'll be submitting this to the GS leadership this week and fully expect them to tell me to shorten some sections and lengthen others. History will likely get the axe and stories get expanded.