How did Norman castles improve security?

All images are labelled for reuse from google images.

In this lesson students will consider the significance of Norman castles in helping William take control of the English. Students start off by drawing and labelling a sketch of a castle and attempting to design it to it is as effective a defence as possible, They will then consider the reasons why castles were so important to William and will consider the advantages and disadvantages of Motte &and Bailey castles. Students will go on to play a game where they will identify some images of Windsor Castle and consider why it's significant. Finally they are asked to place themselves onto a significance thermometer where they will be asked to justify their opinions.