Here's a little something to try - some online visual games (some printable) to give the children's eyes (and yours) a bit of a work out. Visual processing is vital for development of cognitive skills. Exploring and playing with such media then is great for not only the developing brain, but the adult one as well.

Personally I really struggled with getting that ball on the seal's nose! If you want to test yourself, the site provides some links to those infuriating stereograms and many other interesting, fun and useful sites that provide activities and resources for exploring visual processing - warning though, some can be quite addictive! Nothing like a little visual play to brighten your day! Enjoy!