However, students do not develop strategies in isolation. Methods of solution are
constructed in a social context in which students share their strategies with one another. In
Baek’s study (1998) of student development of algorithms for multi-digit multiplication, students
develop their own procedures through sharing different ways of solving problems and discussing
the mathematical meaning underlying their inventions. Students may use mental procedures,
manipulatives (play money or bingo chips), pictures, or written procedures to solve their
problems. Students work on problems individually or in small groups, and then share their
personal strategies or algorithms, discuss similarities or differences among them, and explore
underlying mathematical concepts. Further, as students share their strategies they provide
teachers with a window into how they think about the operational composition of numbers
(Baek, 1998; Carroll, 1996; Willis & Fuson, 1988).