This interactive Java learning tool, which was constructed using the cross-platform open educational resource GeoGebra, allows a teacher to demonstrate and explore addition and subtraction of integers from -10 to 10 with a number line model with students. Users can change the values of the first and second term using sliders. Another option models subtraction of the first term, for example, - (-4) + (-5). Check boxes allow users to show each expression, model, and answer individually.
Keywords:Algebraic representation,Make use of structure,NSDL,Grade 5,Addition,Express regularity,Representation,Number concepts,Social Sciences,Arithmetic,Analyze and persevere,Concept formation,Process skills,Number and operations,Visual representation,Algebra,oai:nsdl.org:2200/20140728160743071T,Critical thinking,Subtraction,Modeling,Informal Education,Integers,Middle School,NSDL_SetSpec_ncs-NSDL-COLLECTION-000-003-112-027,Comparison of numbers,Practice Standards,Grade 6,Elementary School,Reason quantitatively,Algebraic thinking,Operations,Mental calculation,Upper Elementary,Communication,Mathematical language,Grade 7,Mathematics,Engineering,Vocational/Professional Development Education,Expressions,Education,Reasoning