Lots of interactives
http://illuminations.nctm.org/Search.aspx?view=search&type=achttp://illuminations.nctm.org/Search.aspx?view=search&type=ac Search by grade.
Among them:
Creating your own graphpaper/ number lines. Download your creation as jpeg file.
Analyzing Data with Bar Graphs, Line Graphs, Pie Charts, and Pictographs
Creating Equivalent Fractions by Shading Squares and Circles
Exploring Several Different Representations for Fractions
Manipulating Various Geometric Solids and Investigating Their Properties
Creating a Spinner to Examine Experimental and Theoretical Outcomes
Exploring the Number of Chairs Needed when Tables Are Arranged in a Restaurant
Examining Various Two-dimensional Figures to Determine Which Ones Can Be Folded into a Cube
Determining the Volume of a Box by Filling It with Cubes, Rows of Cubes, or Layers of Cubes
Creating a Customized Histogram with Your Own Data or an Included Set of Data
Creating Dynamic Drawings on an Isometric Dot Grid
Drawing, Cutting, Sliding, Turning, and Flipping Shapes (tesselation)
Multiplying Single-digit Numbers with an Interactive Multiplication Table
Algebra tiles
Mean and median (average)
Average (game 4 for mean)
http://www.bbc.co.uk/bitesize/ks2/maths/data/mode_median_mean_range/play/