國小數學學習困難學童之心理數線表徵發展及其數線估計能力之研究

Mental Number Line Representation and Number Line Estimation by Elementary Students with Mathematical Learning Difficulties

本研究目的在於探討國小數學學習困難學童之心理數線表徵發展及其數線估 計能力表現，研究指出，「數字在數線位置估計作業」所探討的心理數線表徵發 展與數線估計能力（以估計誤差量作為指標）是研究學童數感能力的方式之一， 然本研究以電腦化方式進行施測，得以進一步分析數線估計速度表現，並以三種 方式進行分析，團體、個別、嘗試次。所有國小二年級與四年級的受試者都經過 兩次數學與閱讀測驗，結果均低於百分等級35 以下所篩選為數學學習困難合併閱 讀困難、單純數學學習困難、單純閱讀困難、以及正常發展等四組學童。研究結 果指出，有數學學習困難之學童在國小二年級時，其心理數線表徵仍依賴模糊表 徵（介於對數和線性表徵之間），然無數學學習困難之學童已依賴線性表徵；到 了國小四年級，四組學童均已依賴線性表徵，顯示國小二年級數學學習困難學童 之心理數線表徵有發展遲緩現象，但是到了國小四年級則能跟上同儕的發展。至 於估計誤差量與估計速度之數線估計能力，在國小二年級與四年級有數學學習困 難學童之表現均顯著低於無數學學習困難學童，顯示隨著年級發展，有數學學習 困難學童之數線估計能力仍顯著低落，此能力似乎為其核心缺陷。據此，本研究 針對數學學習困難學生的數感能力研究、診斷與教學提出具體的建議。

Purpose: Mental representation of numbers is considered to possess not only quantitative but also spatial properties; therefore， researchers have designed various tasks to estimate it. Mental number line representation， derived from the Spatial- Numerical Association of Response Codes effect， compresses large numbers as logarithmic functions， according to Dehaene (1993). The linear function becomes dominant as children grow. Therefore， this study investigated the development of mental number line representation and number line estimation in elementary school students who have mathematical learning difficulties (MLD). These types of representation and estimation assessed with the “number-to-position” task have been recommended as indicators of number sense in the literature. Methods: A computerized number-toposition task was designed using the Visual Basic program， and performance and speed were recorded when participants indicated the positions of numbers in lines shown on the screen. Four groups of students in the second and fourth grades were screened. Standardized mathematical and reading tests were administered. A cut-off score of