Teaching meiosis presents challenges for both teaching and learning because it is an abstract concept that requires visual and tactile models for most students to conceptualize. The exchange process of maternal and paternal alleles during cross-over is especially difficult without such a reference. A lot of time was spent designing, testing and refining this kit in classrooms to meet your needs. This kit will make teaching and learning meiosis much more enjoyable for you, just as it has for others. This kit includes: A) Teacher Demonstration Models: Thirty large chromosomes arranged in five colorful sets that can seen on your board from the back of your classroom. Each set consists of a maternal and paternal homolog and four sister chromatids. Alleles and parental lineage are clearly identified. The fifth set has removable alleles for demonstrating cross-over. B) Student Models: Students carry out teacher directed assignments at their desk using their own smaller sets of chromosomes. There are no consumables so the kit can be used over and over again. C) Instructional CD and Teacher Manual: We will walk you through using the kit for the first time in an easy, familiar and pictorial slide show fashion. Don't worry if this is your first time teaching meiosis because absolutely everything you need is in the kit. Recommended student activity and assessment options are also included. We even provide a student activity sheet that you can copy. Shipping weight 7 lbs., Dimensions 21" x 19" x 5".