Cut a sheet of A4 in half lengthwise and then fold in half again.
Folding the concertina sides start below.
Fold about 7-8 times.
Fold both of them to make both arms of the tunnel book.
Stand them up. Cut out a back and a front ( The front is trimmed to look like a frame and paste both of them on the back. The back one would have a picture of the sky. in this instance I'd have a daylight scene.
The front can be decorated to look like a frame.
Write a story on the front flaps which can be folded over and a title written on the front.
Two scenes of Harry Potter at the Dursley's waiting for Hedwig to arrive. You could have 4or 5 partial scenes.
Students could write a re-tell of the scene on the arms which fold over the front frame. On the outside you can write the title.
I'll make one with cover paper and proper illustrations to use as a guide for the students. ( The scene with the troll in the toilets or the centaurs in the Dark Wood would be ideal.)