My 5.75 year-old son is really into fact books, and was thrilled when this first arrived. He's enjoyed several pages, but does find the rather dense/busy layout a bit too much at this point. Also, although the Brainwaves are cute, at his age and with slight Aspergers' tendencies he finds them a bit confusing in that they suggest an unreal sense of scale. For now it's been temporarily abandoned in favour of the simpler Usborne lift-the-flap books (which, incidentally, also occasionally feature mini-figures). However, I'm certain he'll love revisiting this one when he's bit older.