The Escuela Nueva (New School) model, introduced in Colombia 40 years ago, is almost unknown in the U.S., despite international accolades for its learning-by-doing approach. Teachers, parents, and students also have a say in how the school is run. While most of the students are poor and live in rural communities, they do as well on reading and math tests as their middle-class urban counterparts. A move is afoot to bring the model here.