Congruent
Congruent are figures that have the same size and shape.
For example, click
here and here.
ELab,
Congruent Figures (Harcourt 3)
Similar
and Congruent Figures: Harcourt School Older

Graphing
Coordinates (x, y) / Cartesian Coordinates (Algebra)
Graph
Mole  Easy Version
Graph
Mole  Medium Version
Graph
Mole  Hard Version
Can be used for younger grades
Using
a Coordinate Grid (Harcourt 4)
Graphing
Integers (Harcourt 5)
Graphing
Integers (grade 5) Harcourt
Type in the correct x and y coordinates:
Catch
the Fly Game
Locate
the Aliens 
Fractions
MathPlay.com:
Math Fractions Games
Visual
Fractions Games
Lesson
Coolmath4kids:
Improper Fractions
Sheppardsoftware
Mathman  Convert Improper_Fractions
Mathgames.com:
Convert Between Improper Fractions and Mixed Numbers
Mr.
Nussbaum: Mixed Numbers and Improper Fractions
More Challenging Games
Mathplayground:
Convert to Improper Fractions
Remember to simplify your answers.
Mathplayground:
Convert to Mixed Numbers
Remember to simplify your answers.
Mathplay.com:
Changing Fractions and Decimals to Percents Millionaire
Game
Unlike Fractions (Least Common Multiples  LCM; Least
Common Denominators  LCD)
ELab:
Addition and Subtractions of Unlike Fractions
Including an activity to complete.

Perimeter
Adam
Ant Explores Perimeters Basic skills
Interactivate:
Perimeter Explorer @ Shodor
Activity
Now, locate something inside or outside of the house
(classroom). Find a ruler and measure the perimeter of
the object that you located (e.g.: paper, book, door, box,
etc.).
If you like, you can just use your feet heel to toe. 