Adding/Subtracting – Help your child develop essential early mathconceptsProduct InformationGive your children the skills they need!Working at their own pace children will develop problem-solving skillsunderstand math symbols and learn how to use numbers up to 100.They’ll get plenty of number practice with these absorbing games and challengingactivities and a system of rewards and positive reinforcement helps your childgain confidence in early math skills!Key Benefits Learn and practice the fundamental concepts  of adding and subtracting Develop problem-solving skills Intelligent software adjusts every game to the child’s ability to respond to their individual strengths and weaknesses Includes printable worksheets and built-in progress trackingProduct HighlightsMath MachineA game that gently introduces numbers and symbols in a fun way.SupergameThe exciting bonus Supergame is reached when all four games have been pleted.It encourages speedy mental arithmetic.Sum It Up!Get a “hands-on” feel for addition with real objects.Count ItDown!Click to remove moving objects for an exciting introduction to subtraction.Solve It!Solve arithmetic problems as well as hidden puzzles.Windows Requirements 486DX/33MHz or higher Windows 95/98/Me/XP 16MB RAM 640 x 480 pixel 256 color screen display 8-bit sound card 10MB of available hard drive space Double-speed CD-ROM drive Loudspeaker or headphones Mouse Macintosh Requirements 68LC040 25MHz  System 7.01 to 9.1 Minimum of 8MB RAM 10MB available on hard drive 8-bit audio 640 x 480 pixel 256 colors Double-speed CD-ROM drive 16-bit sound card Loudspeaker or headphones Mouse