Librería Samer Atenea
Librería Aciertas (Toledo)
Kálamo Books
Librería Perelló (Valencia)
Librería Elías (Asturias)
Donde los libros
Librería Kolima (Madrid)
Librería Proteo (Málaga)
A 30 day, developmentally-based, unit for teaching addition and subtraction with regrouping to second graders. This unit uses problem solving and student discourse as a means to help children to build conceptual understanding around addition and subtraction.