“…Several qualitative studies on bilingual mathematics learning processes have illustrated that students' home languages can be a resource for mathematics learning in various ways, such as participating in mathematical discourses (Planas, 2014), activating everyday out of school experiences (Domínguez, 2011), upgrading resources for meaning making processes (Clarkson, 2006;Norén, 2015), and others (Barwell, 2009, for several possible effects). However, little quantitative evidence exists: Some randomized control trials have provided evidence for the higher efficacy for bilingual teaching programs for other school subjects (Slavin & Cheung, 2005, although many have been criticized for methodological biases; see Rossell & Kuder, 2005), but for mathematics learning, this evidence has not yet been con-vin-cing (Reljić, Ferring & Martin, 2015).…”