From The Physics Teacher: NSCL/JINA's "Marble Nuclei"

The February issue of AAPT's journal, The Physics Teacher, features an article about NSCL/JINA's model nuclei built from magnetic marbles. "Learning Nuclear Science with Marbles" introduces the reader to multiple hands-on demonstrations of nuclear properties using the model. These demonstrations have been used extensively throughout NSCL/JINA outreach programs, and over 100 science teachers are currently trained to use them as part of their classroom curriculum. The full article is available for free online.