We found these on the net for you

We have been surfing the internet for you and have discovered some original, useful and educational sites. Have fun with our suggested links!

1 1 Optical illusions

I can see something you can't see. On his website, Professor Michael Bach from the eye clinic at the University of Freiburg presents numerous entertaining examples of optical illusions which never cease to amaze:
http://www.michaelbach.de/ot/index-de.html

2 Do you just think you are thinking?

Are you open-minded - or do you just think you are? Psychologists examine this and similar questions using the so-called "Implicit Association Test" (IAT). This website presents the method and gives you the opportunity to test yourself:
https://implicit.harvard.edu/implicit/germany/

3 Facts, facts, facts

Not everything the secret services know is in fact secret. The CIA World Factbook is an excellent resource for anyone looking for basic information on a particular country. This English-language website provides comprehensive and up-to-date information for anyone who is interested:
https://www.cia.gov/library/publications/the-world-factbook/index.html

4 Games

Both the following on-line games are in English - but do not require any particular language skill. Guaranteed to be non-violent, they are free and highly original:

The Impossible Quiz

Takes a while to load, but is well worth it. Can you achieve the impossible?
http://www.newgrounds.com/portal/view/365143

The Mystery Of Time And Space - MOTAS

Warning - highly addictive: your task is to solve various tricky puzzles to help find your way through the many doors of an abandoned building.
http://www.albartus.com/motas/