Problem solving, introduced in every grade and practiced throughout elementary school, is an essential foundation on which students build their understanding of mathematical ideas, operations, and relationships. This article discusses 1-2-3 Time, an instructional mode that promotes multimodal math learning in ways that engage and sustain students' interest through its mix of activities and flexible time allotment. Using 1-2-3 Time instructional mode to teach mathematical problem solving to elementary school students, teachers integrate computer technology, children's literature, board games, and writing into their daily teaching. The 1-2-3 Time instructional mode combines direct teaching, interactive games, and independent student learning activities to promote problem solving at the elementary school level. Teachers have time for direct instruction with smaller-sized homogeneous or heterogeneous student groups; students have opportunities to work independently, learn with computers, and present their creative writing to classmates. Problem-solving coaches, math learning games, and reading and writing activities are also discussed. (Contains 2 figures.)