You can put a hole in the wooden box to make it lighter. By removing some material from the box, you will reduce its weight.
A hole can be put into a box to make it lighter. By removing material from the box, its overall weight will decrease.
You can put a hole in the wooden box to make it lighter by reducing the amount of material in it.
You can put a small piece of flint and steel inside a box to create a spark for lighting a fire. Alternatively, you can place a lighter or matches inside a box to provide a convenient way to light objects.
a torch
Termites.
Well you could remove the air from the metal box and put a very light gas in it such as hydrogen or helium that would make it marginally lighter, but I suspect given that these puzzles are mostly riddles that the answer we need here is lighter fuel, thus turning the metal box into a lighter?
Fire always works for me --------------------------------- Normally you would take things OUT of a box to make it lighter.
Holes or spaces can be added to a box to make it lighter without changing its physical contents. This reduces the overall weight of the box without altering the items inside.
a lightbulb
Less.
look on riddles to ponder