Lego pyramids
What can't we do with Legos? We already have a Kenyan city, near the trees of Wangari and the snows of Mt. Kenya, and a train that carries visitors south to Victoria Falls, and now we have the Pyramids of Giza. All three. Creating Pyramids doesn't really require a lot of "how-to" but here's how we did anyway.
We started with a flat sheet and built a base that was 28x2 on all sides. For each subsequent layer we stepped in one row. In order to make it usable for play he needed to be able to reach the inside so we left a doorway by not finishing one wall, and we also made the tip removable. No sooner had we finished the first pyramid than he mentioned the need for three pyramids if indeed this was to be Giza. That took a bit more doing, since we were running of materials, but we managed it. The only thing we couldn't do was make the tip easily removable, since we were out of the smooth thin pieces, but the other two pyramids are smaller (as they are in Giza, mind you), and that step wasn't as necessary.
Appropriately we happen to have one mummy, one pharaoh, one safari explorer, and two explorer pilots in our minifigure collection. The camels, however, were our own creation. Don't laugh.
To make the tip removeable we stabilized it with two platform pieces, then limited the point at which it snaps in place to just one side by using thin smooth strips on three of the sides and just one dimpled strip on the fourth side.