Online games for the four operations and order of operations

Many of these games practice mental math and logical thinking, and suit best grades 3, 4, 5, and 6.

The four operations

Calculator Chaos
Most of the keys have fallen off the calculator but you have to make certain numbers using the keys that are left.
www.mathplayground.com/calculator_chaos.html

ArithmeTiles
Use the four operations and numbers on neighboring tiles to make target numbers.
www.primarygames.com/math/arithmetiles/index.htm

Choose Math Operation
Choose the mathematical operation(s) so that the number sentence is true. Practice the role of zero and one in basic operations or operations with negative numbers. Helps develop number sense and logical thinking.
www.homeschoolmath.net/operation-game.php

MathCar Racing
Keep ahead of the computer car by thinking logically, and practice any of the four operations at the same time.
www.funbrain.com/osa/index.html

The Crazy Counting Machine
Make the target number by doubling, halving, adding 7, or subtracting 3.
www.crickweb.co.uk/assets/resources/flash.php?&file=crazyc

Math Scramble
Arrange the given numbers into the equation to make it true.
www.spacetime.us/arcade/play.php?game=3

Number Pyramid
Arrange the bottom numbers of the pyramid in order to achieve the highest/lowest possible number on the top.
www.crickweb.co.uk/assets/resources/flash.php?&file=PYRAMID3

Mental Math Techniques
An article explaining a few simple mental math strategies suitable for grades 3-6, like breaking numbers apart, or 'compatible numbers', with exercises.
www.phschool.com/professional_development/mathpd/pdfs/math_across_the_grades.pdf

Fill and Pour
Fill and pour liquid with two containers until you get the target amount. A logical thinking puzzle.
nlvm.usu.edu/en/nav/frames_asid_273_g_2_t_4.html

Math Mountain
Climb to the top of the mountain by answering simple math questions faster than your opponent (computer or human).
www.spacetime.us/arcade/play.php?game=23

Quick Calculate
Practice your arithmetic of all four operations plus order of operations. themathgames.com/arithmetic-games/addition-subtraction-multiplication-division/quick-calculate-game.php

The Abacus
History, instructions, articles about the age-old calculating aid.  
See also an interactive Java applet with a demo showing how counting and calculations are done. Nurtureminds.com sells workbooks that teach abacus.
www.ee.ryerson.ca:8080/~elf/abacus/index.html

Order of operations
Mystery picture game.
www.dositey.com/math/m/mystery2SMA.htm

Bitesize Revision - Numbers
Has summary-type fact sheets/flash movies and little interactive test for understanding on several subjects: subtraction, addition, division, multiplication, fractions, number system, percentages, etc.   Very nice and appealing graphics.
www.bbc.co.uk/schools/ks2bitesize/maths/number.shtml

Online math tutors to help with math homework are available 24/7 at Tutor.com.

Online math resources menu
	Addition and subtraction Place value Clock Money Measuring	Multiplication Division Math facts practice The four operations Factoring and number theory Geometry
	Fractions Decimals Percent Integers Statistics, Graphs, and Probability	Geometry Algebra Calculus Trigonometry Logic and proof
	Problem solving & math projects For gifted children Math history	Math games and fun websites Sites with interactive math tutorials Math help & online tutoring Review and test prep Online math curricula