activityprograms americansignlanguage casestudies childdevelopment children earlychildhoodeducation educationalgames englishlanguage interactionanalysisineducation interculturalcommunication language languageandlanguages languagedisordersinchildren listening secondlanguageacquisition signlanguageacquisition studyandteaching studyandteaching(earlychildhood) studyandteaching(elementary)