The magician shows six different coloured Smarties (or other sweets) and an unopened box of sweets. A spectator selects one of the sweets, and when the box is opened and the sweets tipped out, they are all Smarties of the colour the spectator chose.
An easy prediction trick, and one where you can eat the props afterwards – or give them away to your lucky spectator.
You can also view this trick on YouTube at https://youtu.be/HrUso3tv1f8
You can see all the previous magic lessons here.