Chairperson, Graduate Committee: Greg FrancisPatton, Rachel Lynn2021-11-162021-11-162020https://scholarworks.montana.edu/handle/1/16329This action research aimed to answer the question, are students able to learn and apply vocabulary that was not pre-taught but was instead introduced at the moment students needed the vocabulary. This research also examined whether there were differences in the vocabulary scores of English Language Learners (ELL) and non-ELL students. Students completed a science vocabulary pre-test for vocabulary related to nuclear chemistry and chemical bonding. Then, over the course of the two units, students completed guided inquiry activities which explored the concepts of nuclear chemistry and chemical bonding. Vocabulary was introduced after students had explored these concepts, and the terms were defined and added to student vocabulary trackers and the class word wall. At the end of each unit, students completed a vocabulary post-test, which consisted of both recall and application questions. At the end of the second unit students were asked to complete the survey assessing attitudes toward this method of instruction, and a small percentage of students also participated in an interview. Both ELL and non-ELL students showed statistically significant gains from pre-test to post-test in both vocabulary knowledge and confidence. Results indicate that students effectively learn content vocabulary even when the vocabulary is not explicitly pre-taught.enChemistryHigh school studentsInquiry-based learningContent area readingVocabularyLanguage and languagesProfessional PaperCopyright 2020 by Rachel Lynn Patton