Idea for when it's summer

Get together when it's late night and dark out, go to yard and burn things to see the pretty colors. Prep needed: review chemistry for good color producers. Procure a few small safe fire-sources to space out in a line (so we won't have to crowd around one). Gather materials; some can be assigned to guests to bring. Have flashlights and water/extinguishers on hand. Optional: thematically appropriate movie to watch indoors while we wait for evening light to end.