In World Around us P4 investigated which materials would have been most suitable for blackout curtains in WW2.We used a light box and tested a range of materials over it. We scored them from 0 or 1 (lets all the light through) to 5 (not allowing any light through).We sorted the materials into three groups: opaque, translucent and transparent. We discovered dark colours worked best and that using layers was good. The best materials in this experiment were tin foil and dark blue towelling.
