Sheila Scafine(middle), a calculus teacher at Serra High School in San Mateo, solves the rubic cube with students, Michael Wise(left) and Carlo Dacanay during a lunch period competition Wednesday with other students. John Green/San Mateo County Times

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Sheila Scafine(middle), a calculus teacher at Serra High School in San Mateo, solves the rubic cube with students, Michael Wise(left) and Carlo Dacanay during a lunch period competition Wednesday with other students. John Green/San Mateo County Times
ZUMA / Alamy Stock Photo
Image ID: DKDPFM