Keeping Up in Class With Software for a Hand-Held One of the most common student uses of a hand-held computer is to keep track of assignments and grades. Due Yesterday (www.due-yesterday.com), $15, and 4.0Student (www.handmark.com), $19.99, are good replacements for pocket calendars. Both provide tools that allow you to enter information about courses, including meeting times, contact information for professors and assignments. They offer views of due dates that can be customized by the week, by individual course or with all classes included. Assignments and test dates can be exported to the Palm's datebook and to- do list with either program, allowing students to coordinate schoolwork with the rest of their lives.