Walmart has this K’NEX Education: Middle School Math Building Set for only $86.76 (Was $150) plus free ship. ping or free in store pickup. The K’NEX Middle School Math set is designed to address critical mathematics concepts in the middle school classroom and to provide instructional models that will enhance students’ understanding of important concepts and algorithms. With direction provided by the teacher’s guide and the materials provided in this set you will be able to offer students a program of study that uses hands-on exploration in conjunction with an inquiry-based approach to learning. The guide also includes additional information that teachers will find to be invaluable as they seek to motivate students to explore, experience and learn mathematics. Set includes 1,245 K’NEX parts — enough to build 115 math and geometry models! Builds up to four models simultaneously.