We know the struggle with mathematics—for both teachers and students—all too well. Students’ math scores, as per the “Nation’s Report Card,” have plunged to record lows. Misconceptions in early grades ...

The letter “x” often symbolizes something unknown, with an air of mystery that can be appealing. Illustration by Meilan Solly Even though “x” is one of the least-used letters in the English alphabet, ...

New studies of the “platypus of materials” help explain how their atoms arrange themselves into orderly, but nonrepeating, ...