“…Likewise, the teachers' professional skills consist of multiple sub-contents (Vegas, 2005) that have been shown to impact children's learning: teacher's own mathematical skills, teacher's self-efficacy, values and attributes (Araya, 2014), as well as pedagogical skills and knowledge (Javier & Manuel, 2015), teacher's knowledge about learning difficulties (Balbi, Ruiz, & García, 2017), or abilities to tailor instruction to each student's needs in learning (Gallego, Näslund-Hadley, & Alfonso, 2018). Countries with strong policies for assuring the quality of teachers are also found to be among the strongest performers on international tests of mathematics achievement (Ingvarson & Rowley, 2017).…”