“…Children, and even some adults, exhibit misconceptions about the complex conceptual structure of fractions (Ni & Zhou, 2005;Siegler, Fazio, Bailey, & Zhou, 2013;Siegler, Thompson, & Schneider, 2011;Stigler, Givvin, & Thompson, 2010). Such difficulties have also been reported in high mathematicsachieving countries such as South Korea (Kim & Whang, 2011Kwon, 2003;Pang & Li, 2008). Students also encounter problems in learning to understand decimals (Rittle-Johnson, Siegler, & Alibali, 2001), but generally master the magnitudes of decimals before fractions (Iuculano & Butterworth, 2011).…”