The K12 Let's Learn Rhythm/Sing Home School Music Curriculum CD-ROM 2003 is a software product that includes 4 CDs. It is an Arts & Culture educational tool that teaches rhythm and singing in English. The software is compatible with Microsoft Windows 95 and Mac operating systems. The product was manufactured in the United States and is designed for home schooling purposes. Let's learn rhythm is the only one that is open, very good condition. The others are sealed. Please read the back of the case as it needs certain tech requirements . The other cases indicate that they are compact disc, digital audio.The cases have some wear. Pictures are the best description of details and condition. If you have any questions send me a message and thank you for looking.