opportunities to practice certain interaction behavior, may have helped them to improve their interaction skills, which then resulted in a positive change in their children’s receptive vocabulary.
Technology-enhanced learning activities, in which parents were provided real-time interaction support, seemed to have had a similar effect on parents’ interaction skills and children’s vocabulary development. Previous studies showed that programs focusing on parents are less likely to have positive effects compared to programs directly focusing on children’s vocabulary development (Blok et al., 2005). The current results are important because they demonstrate that, via indirect approaches that target parents, vocabulary changes in the child can be achieved. To establish positive effects on children’s vocabulary, a systematic change in parent’s interaction behavior is required. Parent group meetings including AL and TL apparently facilitated these changes in parents’ interaction behavior with their children at home during literacy activities.
The positive changes in children’s receptive vocabulary via AL and TL, are consistent with those of previous studies that showed improvement in receptive vocabulary after training parents with active learning and technology-enhanced activities. In their meta-analysis, Grindal and colleagues (2016) found suggestive evidence that systematically modeling and practicing interaction behavior with parents was associated with effects on children’s pre-academic knowledge (such as reading and letter recognition). The positive effect of AL in our study provides support for this suggestive evidence. With respect to TL, previous research (Gremmen et al., 2016; Teepe et al., 2016) found that technology-enhanced storytelling, where parents received real-time interaction support, fostered parent- child interaction quality and children’s vocabulary development. However, these studies involved artificial learning contexts in which parent training was provided by researchers rather than teachers. The current study shows that, within the complex home setting of a naturalistic educational situation, TL may also work. It can be concluded that both AL and TL are effective for stimulating children’s receptive vocabulary development.
We found no positive effects of AL and TL on children’s productive vocabulary development. A first explanation for this is based on the assumption that vocabulary exists in a continuum, in which receptive vocabulary is seen as a precursor for productive vocabulary (Nagy & Scott, 2000). We propose that children have acquired an understanding of the words’ meanings, but that they were not yet able to actively use it and apply it in the appropriate context. It could be that effects on productive vocabulary occur at a later moment in time.
Another explanation for this finding is related to how AL and TL affected parents’ interaction behavior. In both approaches parents were trained to provide linguistic input and to involve their child in verbal interactions at home. The effect on children’s receptive vocabulary indicates that parents indeed provided sufficient linguistic input for their child to encode linguistic input, match phonological representations to referents and store the links in their working memory (Sénéchal, Thomas, & Monker, 1995). However, for productive vocabulary development to occur, the child also needs to be offered opportunities to retrieve words from their working memory, by practicing and being verbally active in social interactions. In spite of parents’ efforts to interact more with their child, we hypothesize that both variants of the program may have supported parents insufficiently to activate their child’s verbal interactions. Parents may have been too dominant in conversations with their child, leaving too few opportunities for children to retrieve words from their working memory and to use them during interactions.
This idea is supported by previous research showing that parents tend to be the dominant speaker when interacting with their child (Hoff, 2006; Teepe et al., 2016). Even though the program supported parents in improving their interaction behavior, the program should train parents more intensively to leave more room for their child to verbally participate in the interaction, by, for example, further stimulating the use of open-ended questions. The current result, a positive effect on receptive vocabulary but no effect on productive vocabulary, indicates that children involved in AL and TL have received sufficient linguistic input to develop their receptive vocabulary, but have been offered insufficient opportunities to produce output for developing their productive vocabulary.
It should be acknowledged that the positive effect of AL and TL on children’s receptive vocabulary development is limited. Experimental children learned on average two of the selected 16 words per theme (12%) compared to control children who learned one word (6%). However, considering that, on average, nine of the 16 words were already known at pre-test, the learning gain is larger. It might be more appropriate to say that two words (experimental children) and one word (control children) out of seven unknown words were acquired within six program weeks. That way, experimental children expanded their vocabulary by 29% compared to control children expanding their vocabularies by 14%. In the light of the total number of words offered within each theme (about 225 words per theme), this could mean that, per theme, experimental children learned about 65 words whereas control children might have learned approximately 32 words in six weeks. It is expected that the vocabulary growth