The iPad may have come out only a year ago, but its applications are being developed very rapidly. Already there are a number of iPad science apps that can help schoolchildren from grades K thru 12 learn in a way that can be very enjoyable. And many of these iPad science apps are very cheap, too: Some of them cost as little as $1.99, or are even given for free! Some iPad science apps will be discussed in this article. Most of them deal with astronomy, but there are apps for other sciences as well. Star Walk is an excellent tool for exploring the night sky. The iPad itself has a built- in compass that can be used to show the relative positions of the stars, planets, and other celestial objects at any given latitude, at any given time of night. (And if your iPad is equipped with a Camera Connection Kit, you can also use the same device to take telescopic photographs of planets and moonsâ€” and display them on a large screen or monitor via a Digital AV Adapter!) Star Walk is one of those iPad science apps that are excellent for teaching children of all ages. Solar Walk 3D and iLearn Solar System HD are two iPad science apps devoted to teaching about our solar system. The former is by the creators of Star Walk (above) and some of its images can be viewed with special 3D glasses. The latter app is specifically for elementary school children; information is narrated by an animated astronaut who is accompanied by a large- nosed, blue extraterrestrial. Moving on to iPad science apps for other fields, we have 3D Brain, which as, its name indicates, takes users on a three- dimensional tour of the human mind, showing how each part functions. Parents of children with mental disorders might also find use for this app, which is free. Periodical Table of the Elements is also free. From the periodic table, one can choose any element and find not only its basic chemical properties, but also a visual representation of its atomic structure. There are many other iPad science apps out there. These include Newton's Cradle, a simulation of a device invented by the scientist to illustrate the principles of momentum; Supernova, showing the process by which a huge star finally ends its life; Science in 3D. And no doubt other educational science applications will be made for iPad in the days to come. As you see, iPad science apps can be a great educational tool for your schoolchild. And what is most convenient is that everything can be stored on just one device small enough to fit into the pocket!