teaching resource

Mental Math – Subtraction Flashcards

A set of 36 subtraction flashcards using one- and two-digit numbers.

These flashcards can be discussion points for students to decide which mental math strategies best solve the equations. Alternatively, each subtraction equation can simply be solved.

The flashcards have been designed to practice the following strategies:

• counting back
• compensation strategy
• split strategy
• compatible numbers
• decomposing to a ten
• using the inverse operation (fact families) to solve.

While most flashcards contain the minuend and subtrahend, some flashcards have one of these missing and provide the difference instead.

Curriculum

• CCSS.MATH.CONTENT.2.OA.B.2

Fluently add and subtract within 20 using mental strategies. By end of Grade 2, know from memory all sums of two one-digit numbers.

• CCSS.MATH.CONTENT.2.NBT.B.6

Add up to four two-digit numbers using strategies based on place value and properties of operations.

• CCSS.MATH.CONTENT.3.NBT.A.2

Fluently add and subtract within 1000 using strategies and algorithms based on place value, properties of operations, and/or the relationship between addition and subtraction.