Tie a trefoil knot in a piece of string, seal the ends together, and try to wiggle it free without cutting. In three-dimensional space, the knot holds firm. Add a fourth spatial dimension, however, ...

A tentative new elementary school schedule would increase English instruction by roughly 15 minutes a day, and math by 20 ...

From arts to science, computer to sports, dance to theater, there are plenty of options to keep kids entertained.