Despite many studies on students' understanding of the equal sign, little attention has been paid to whole-class discourse on their conceptions of equations with two equal signs. This study analyzed the classroom discourse of 30 fourth graders in Korea who participated in a 5-week classroom teaching experiment. A series of discussions on specific equations with two equal signs showed that the students had subtle but significantly different conceptions of the equal sign, even though they often shared the common approach of saying "is the same as" when referring to the equal sign -- these findings differ from previous studies. Classroom discourse exposed the simultaneous coexistence of various conceptions in a single student's mind, including both operational and relational conceptions of the equal sign. The study's findings argue for and demonstrate the value of learning opportunities to explore equations with two equal signs in a systematic and explicit way.