These books are a cry of relief from the five minute books we usually read with our son and they have already taught him so much about science, nature, and particularly history. Jack and Annie, the lead characters in the series, travel through time and meet with prominent historical figures such as Equipment Queens, take a trip to the moon, spend a day with Abraham Lincoln, land in camp with General George Washington as he is ready to cross the Delaware, and even convince a young Mozart to continue his pursuit in music.
They are well written books that peak interest in subjects young kids may not yet have access to and have accompanying research guides that give detailed back stories and historical guides to the subjects covered in the novels. Although the intended audience of the series seem to be for children around 8 - 10, our five year old becomes engulfed in the stories every single evening, always looking forward to what adventure Jack and Annie are heading for next.
Amazon also tend to have a wider availability of the series than book stores like Barnes and Nobel at prices up to half the cost of the same.