Young children are thought to play a unique role in the emergence and evolution of language. In research on language acquisition by a deaf child of late learners of ASL as well as in research on the emergence of new signed languages, young children have shown the ability to impose systematicity on relatively less systematic linguistic input (Singleton & Newport 2004) and to elaborate new grammatical structures that were not present in their linguistic input or that were present to a lesser degree (Senghas & Coppola 2001, Senghas et al 2004). In their account of the emergence of Nicaraguan Sign Language (NSL), R. J. Senghas and colleagues (2005: 303-304) hypothesize that the human ability to systematize and elaborate language (“constructive linguistic abilities”) peaks in childhood (roughly, up to age 10; cf. also Senghas & Coppola 2001). Pre-adolescent “child learners” in Nicaragua, according to these authors, played the principal role in driving the evolution of NSL (Senghas et al 2005: 300). Here we examine a community of signers centered at the American School for the Deaf (ASD), which was founded in 1817 in Hartford, CT and which was the first school for the deaf in the US. As we show, young children were almost entirely absent from that school due to a 19th century policy that, at its lowest, set the minimum age of admission at 8.