Step 1: Master your basic facts:

Mental Math Practice (Grades 4 - 8)

Step 2: Master all the strategies below!!!

Addition

Lesson 1: One Step At A Time
Lesson 2: Using Place Value Names
Lesson 3: Using What You Know
Lesson 4: Break It Up
Lesson 5: Break It Up (Again)
Lesson 10: Starting At The Left
Lesson 12: Working With Fives
Lesson 13: Trading Off
Lesson 15: Searching For Compatibles
Lesson 16: Searching For Compatibles
Lesson 17: Searching For Compatibles
Lesson 18: Make-Your-Own Compatibles
Lesson 19: Think Quarters
Lesson 20: Noticing Nines

Subtraction

Lesson 6: Dropping Common Zeros
Lesson 7: Dropping Common Zeros
Lesson 8: Front-End Focus
Lesson 11: Starting At The Left
Lesson 14: Balancing In Subtraction
Lesson 21: Noticing Nines

Addition & Subtraction

Lesson 9: One Step at a Time

Multiplication

Lesson 22: Tack On Trailing Zeros
Lesson 23: Tack On Trailing Zeros
Lesson 24: Tack On Trailing Zeros
Lesson 25:  Front-End Multiplying
Lesson 26: Front-End Multiplying
Lesson 27: Noticing Nines
Lesson 28: Doubling
Lesson 29: Halving And Doubling
Lesson 34: Think Money
Lesson 35: Searching For Compatible Numbers
Lesson 36: Make-Your-Own Compatible Factors

Division

Lesson 30: Divide By Multiplying
Lesson 31: Tack On Trailing Zeros
Lesson 32: Canceling Common Zeros
Lesson 33: Breaking Up The Dividend