“…Identified cognitive factors include spatial abilities (Clements et al, 1997; Geary, 1996; Jeung et al, 1997; Kyttälä & Lehto, 2008; Purcell & Gero, 1998; Spelke et al, 2010; Verstijnen et al, 1998), fluid intelligence and reasoning skills (Battista, 1990; Dawkins, 2015; Giofrè et al, 2014), working memory (Giofrè et al, 2013, 2014), geometry content knowledge (Bokosmaty et al, 2015; Lawson & Chinnappan, 1994), and meta-cognition (Aydın & Ubuz, 2010). In addition, motivation, persistence, and student emotions (e.g., boredom and enjoyment) are frequently cited to interpret students’ geometry learning difficulties and individual differences (Bailey et al, 2014; Super & Bachrach, 1957). Some pedagogical variables also have been documented, such as the geometry curriculum (Battista & Clements, 1995; Clements & Battista, 1986; Halat et al, 2008; Oner, 2008), teachers’ instructional approaches (Kuzniak & Rauscher, 2011), and task complexity level (Hsu & Silver, 2014).…”