The Coleco Talking Teacher (Released 1985) is a child's teaching aid with a synthesized voice. It has 8 English and 2 maths activities with a total of 165 word's vocabulary built in (Rare as snake knee's expansion cartridges are available) its circuitry is similar to that of the Texas instruments speak and spell range of toys but with more advanced voice chips and functions. luckily for circuit bending the circuit is very bendable unlike the super speak and xox of the same era which have far more advanced circuits and so fewer bends usually available. 
http://www.magicmess.co.uk/cb/talking-teacher.php

Circuit bent Coleco Talking Teacher  by Matt The Modulator

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DataMath  AkA Matthew Newlove - I'm a circuit bender, Audio electronics maker,mixing engineer and school grounds person


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Datamath