The Responsive Model Program uses the typing or learning booth as an important part of its autotelic (self-rewarding) environment, to help children develop the mental processes involved in discovery of relationships, such as the association of sound with symbols, or discovering the rules of a game. The typing booth also helps children to develop…

The occurrence of the two allomorphs of the indefinite article in standard English ("a" before nouns or noun clauses beginning with consonant sounds and "an" before those beginning with vowel sounds) is a concept similar to those studied in the general concept formation paradigm. The acquisition of this grammatical concept was examined using 80…