Use the following steps to see the hidden photos in the background of some levels:
||HOW TO VIEW
||Tap on the peeled wallpaper in the background on the far right side of level 3-19.
||Tap on the peeled wallpaper above the second star in level 2-19.
||"Like" the "Cut The Rope" Facebook group through the link in the Professor's Album.
||Tap the peeled wallpaper in the background on the top left side of level 1-14.