Optical gadgets can help us to see.
They can also change how we see and what we see.
This section consists of an introductory activity 'Seeing things' followed by three activities related to 'How we see'. There is a Summary which will help you reflect on what you have investigated.
Introductory activity: Seeing things
Activity 1: Light rays*
Activity 2: Shadows*
Activity 3: Optical illusions*