NICK MASSI, 73, an original member of the '60s pop group the Four Seasons ("Big Girls Don't Cry"), died of cancer on Sunday. He provided the bass counterpoint to lead singer Frank Valli's falsetto as well as the group's arrangements . . . "Schoolhouse Rock" creative director THOMAS G. YOHE, 63, died of cancer on Sunday. The ABC show, which ran from 1973 to 1985, set educational messages to bouncy music and won four Emmys for outstanding children's informational series . . . British race car designer JOHN COOPER, 77, who developed the rear-engine Formula One racer and the lovable if boxy Mini Cooper (which in the '60s rivaled the VW Bug for cult status), died of cancer on Sunday in England. Celebrity owners of the Mini included Beatles Paul McCartney and John Lennon and "Pink Panther" actor Peter Sellers.