Andy, great to chat earlier
As its's for a short film project I think your daughter could get more marks for being creative and in this case making a film with a coffin in but without using a coffin...
This would require a well planned story board and some clever camera shots.
Walking into a room with a coffin - the scene starts in adjacent room with the door closed, people talking about the situation etc, the shot ends with the person walking into the room with the coffin in and then continues with the camera placed on a table at coffin height so filming from the coffins point of view so capturing the persons emotions etc walking up to the coffin.
Seeing the person inside - this can be done by a close up from above using a shaped cardboard box lined with cheap silk type material from dunelm or something.
Touching the coffin - get a piece of laminated oak from a DIY shop about 16" x 2 ' and may be a brass handle too, the shot would be a closeup of a hand touching or running along the wood or handle.
Carrying the coffin - a close up of someone with the board on their shoulder with one hand up against the side. next shot would be just of the feet of 6 people pretending to walk with the coffin.
Lowering a coffin - a close up of a rope sliding through the handle on your board.
Ashes to ashes - screw a brass cross to your board and then shoot a close up of some dirt being thrown on it.
All other shots should be taken from the coffins point of view / behind the camera. Or heads and shoulders so the coffin is out of view.
She must create an illusion in the audience's mind that without a doubt there is a coffin there leaving them to imagine the rest...
And she must put all this in her course work so the person marking it can see what she has created