Over a four-year period, Boaler followed the progress of seven hundred students through their high school careers at three high schools. One of the three was "Railside High". Not its real name, this school was in an urban setting, close by a railway line. She first visited the school in 1999, having heard that they seemed to be achieving remarkable results, despite the poor location and run-down appearance of the school buildings.
A number of features singled out Railside. First, the students were completely untracked, with everyone taking algebra as their first course, not just the higher attaining students. Second, instead of teaching a series of methods, such as factoring polynomials or solving inequalities, the school organized the curriculum around larger themes, such as "What is a linear function?" The students learned to make use of different kinds of representation, words, diagrams, tables symbols, objects, and graphs. They worked together in mixed ability groups, with higher attainers collaborating with lower performers, and they were expected and encouraged to explain their work to one another. [pp.58-68]
