In the preceding sections, we have reviewed how an active-learning framework can be extended to explain children’s remarkable success at learning language. Here, we list several key remaining questions that we hope will inform future research:
	
How can the mechanisms of self-directed learning in language development be characterized? What do children track to guide their attention? For example, do they rely more on familiarity, or how well they can predict what will come next, or on how simple the structures are? Do children exploit similar signals in other domains?
	
What is different between how an infant and how a preschooler direct their own language learning? What are the relevant developmental processes influencing children’s self-directed learning capabilities? For example, how do developments in working memory come into play?

Is children’s allocation of attention rational? Is it possible to build computational models specifying the optimal allocation of individual children’s attention, given the goal of learning language?

Where can active learning of other aspects of language knowledge be observed? We have focused on the utility of active learning for acquiring the lexicon, but there are no doubt analogies for grammar learning. For example, is there some just-right level of syntactic complexity that best captures the attention of children at a given stage of language development?

How does affect intersect with cognitive motivations for language learning? One promising research area concerns how children’s lexical development reflects their interests (e.g., dinosaur-loving children learn many dinosaur names; Mani & Ackermann, 2018). According to functional accounts of emotions (Barrett & Campos, 1987), children’s attention to fruitful learning opportunities may be driven by a positive affective experience, rather than some metacognitive insight.
