
Julian F. Fleron Model Railroad Train Tracks, Tangles, Dominoes, and Tetris: Deep Mathematical Problems as the Progeny of Children's Toys. |

Rosann M. Tefts The Sphere Packing Problem. |

Suzanne Gallagher (shown) & Kathyrn Matras Busy Beavers in Massachusetts. |

Christopher S. Adams (Shown), Suzanne Gallagher, & J. Ferris Controlling the Population of Black Bears in Wisconsin. |

Philip Hotchkiss Cardboard Boxes, "Elliptic Curves", and the Quadratic Formula: It's Perfectly Rational. |

Brandt Kronholm A New Relationship Between Triangular And Square Numbers. |