Stack and unstack books or boxes

Stack 4-6 books or boxes into a neat pile, then take the pile apart. One round per clip.

Start: 4-6 books or boxes lying apart on a table.

Record: Stack them one at a time into one pile, straighten its edges and let go for a second. Then take the pile apart one at a time.

Done when: The books or boxes lie apart on the table again.

Also counts: Books, notebooks, magazines, food boxes, parcels or containers; the same or different sizes. Send as many clips as you like, changing the items or their order each time.

How: phone on your head (not on your chest or in your hand), both hands free and in view the whole time, good light. One continuous clip of one complete round, about 10-60 sec (max 90 sec). Start recording a few seconds before you begin and stop a few seconds after you finish. Keep the app open until it uploads. Keep faces and documents out of view.

Can be declined if: not first-person, phone held in a hand, hands out of view, the start or the result not visible, the round not finished, or too dark or blurry.