How to Improve 6-Mark Questions in GCSE Science (And Why They Matter More Than You Think) If your child understands the science but isn’t getting the grades they’re capable of, 6-mark questions are often the reason why. In GCSE Separate Science, extended response questions appear on every paper. These questions require students to explain, evaluate, compare or justify – and they are worth a significant number of marks. Across a full set of Biology, Chemistry and Physics paper