“…A large body of Author's copy of the paper as accepted for publication 3 literature has explored the development of children's oral counting skills (e.g., Bruce & Threlfall, 2004;Fuson, 1992a;Fuson, 1992b;Threlfall, 2008), the development of children's counting competencies (e.g., Bialystok & Codd, 1997;Fuson, 1992b;Gelman & Greeno, 1989;Greeno, Riley & Gelman, 1984), and the use of counting as a calculation and problem solving strategy by children of different ages and attainment in mathematics (e.g., Lefevre et al, 2002;Siegler, 2006;Siegler & Robinson, 1982;Sophian, Wood & Vong, 1995). However, there has not been much attention to children's learning of oral counting in steps bigger than 1 (e.g., counting in steps of 2, 5 or 10) and to how children develop this skill into processes that can support their calculations, despite the acknowledged significance of such counting skills (often referred to as "step" or "skip" counting) for mental calculation (Anghileri, 2008;Thompson, 2008).…”