The Casio ClassPad 300, ClassPad 330 and fx-CP400 are stylus based touch-screen graphing calculators. It comes with a collection of applications that support self-study, like 3D Graph, Geometry, eActivity, Spreadsheet, etc. A large 160x240 pixel LCD touch screen enables stylus-based operation. It resembles Casio's earlier Pocket Viewer line. HP and Texas Instruments attempted to release similar pen based calculators (the HP Xpander and PET Project (see TI PLT SHH1), but both were cancelled before release to the market. The ClassPad 300 allows input of expressions, and displays them as they appear in a textbook. Factorization of expressions, calculation of limit values of functions, and other operations can be performed while viewing the results on a large LCD screen. It also comes with graphing tools for 3D graphing and drawing of geometric figures. The user interface features a pull-down menu format. Solutions, expressions, and other items can be selected with the tap of the stylus. Drag and drop, copy and paste, and other pen-based operations, are also supported. An eActivity application allows the creation of so-called eActivities, which can include figures, expressions, and explanations. In the United States the ClassPad series is banned from standardized tests including the SAT, the ACT, and the AP Calculus test, due to its virtual QWERTY keyboard and stylus usage. In 2017, the fx-CG500 was released, targeted towards the North American market. While almost entirely identical to the fx-CP400, its removal of the QWERTY keyboards means it is included in the list of allowed calculators on American standardized exams, including AP and SAT. History During 1996, CASIO worked on the CAS (Computer Algebra System) and studying Geometry. The CAS was first used in the Casio CFX-9970G then the Casio Algebra FX 2.0, and later formed the core math system for the ClassPad. In 1999, the idea of the eActivity emerged. It was intended to allow all applications to interact from within one application, and display information in a textbook style. In 2000, CASIO opened a new office, the CASIO Education Technology M.R.D. Center in Portland, Oregon, USA. They hired many engineers, and started to implement more features. In 2002, CASIO completed a prototype for the ClassPad. Before the prototype was complete, an emulator was used for testing. The emulator was later included in the software that was being developed for data transfer. The data transfer and emulator software later merged into one product called the ClassPad