Martine van der Pluijm

148 Chapter 5 need to adapt activities to the social environment of families and the specific characteristics of lower-educated parents. We trained teachers to explain the activities step by step and to illustrate their explanations by modeling and by avoiding metalinguistic jargon. This tailoring of activities to the specific needs of lower-educated parents is assumed to be effective for our target groups of parents (e.g., Hannon et al., 2019; Manz et al., 2010; Reese et al., 2010). The combination of involving parent and child and adapting parent-child activities to the specific beliefs and skills of the target group might have contributed to the above-mentioned results for lower-educated families. The two studies presented in this paper are complementary and could improve our knowledge of school-based interventions dedicated to involving lower-educated parents in the oral language development of their young children. Study 1 focused on parent perceptions of the program in a heterogeneous sample. In contrast, Study 2 focused on parental behavior in adapted parent-child activities in a homogeneous sample of lower-educated parents. We found no changes in parent perceptions in general. However, we did find improvements in the behavior of lower-educated parents. Limitations and suggestions for future research The findings of this research contribute to efforts of family literacy researchers to understand and support lower-educated families. The main limitation of this research is that it is based on two relatively small-scale studies, focused on respectively seven and four schools in the city of Rotterdam. More extensive and experimental research is needed to investigate how interventions can be implemented effectively to contribute to SFPs in which teachers and low- educated parents collaborate in supporting the oral language development of young children. Future research could focus on experimentally testing interventions for the lowest educated groups of parents. We recommend a phased research design that creates control groups by using a switching replications design (Trochim, Donally, & Aurora, 2014). In other words, all teachers and parents participate in the intervention, but the phase of implementation creates the opportunity to compare the results of groups with and without intervention one after the other. Additionally, future research could investigate whether interventions for the lowest educated parents affect children’s oral language development. We recommend using several instruments that measure both the quantity and quality of oral language development, including vocabulary. A review by Van der Pluijm et al. (2019, see Chapter 2) shows that combinations of measures for oral language development are rarely used in family literacy research. It is also of interest to measure children’s oral language development in the language that migrant children speak at home. Multiple instruments enable us to reveal relevant aspects of children’s oral language development (e.g., Landry et al., 2008). Another issue is that parental literacy skills seem to be underexposed in family literacy research, despite the impact of these skills on language and literacy promotion (cf., Manz et al., 2010). Adequate definitions and