Common Friends, Pull Down Model, Use of Equations, Rainbow Method, etc

3-Step Guess and Check, Double "IF", Excess-and-Shortage, Branching Method, etc

Comparison Model, Make Supposition, Grouping, Gap Problems, Use of Equations, etc

Part-Whole Model, Comparison Model, Working Backwards, Before and After, etc

Part-Whole Model, Comparison Model, Make a List, Look for Patterns, etc

Number Bonds, Part-Whole Model, Look for Patterns, Guess and Check, etc.