Grades 2 to 8
Geoboard
Tap pegs to stretch a rubber band into a shape. Close it to fill it in, and the area and perimeter appear below. Make as many shapes as you like, each in its own color.
Tap a peg for each corner. Tap the first peg again to close the shape. One space between pegs is 1 unit.
Ways to use it in class
- Area and perimeter. Make a rectangle and read both numbers, then change its shape and see which one changes.
- Same area, different perimeter. Make three shapes with area 8 and compare their perimeters.
- Name the shape. Build a triangle with two equal sides, or a quadrilateral with four right angles.
- Slanted sides. Make a diamond and see why its side is longer than one unit.
Questions teachers ask
- What is a geoboard?
- A square board with a grid of pegs. Children stretch rubber bands around the pegs to make shapes. This virtual geoboard works the same way: tap pegs to place the corners of a shape, then close it to see it filled in.
- How do I make a shape?
- Tap a peg to start, then tap more pegs for each corner. Tap the first peg again, or press Finish shape, to close the band. Press Undo point to take back the last corner, and Clear to start over.
- How does it find area and perimeter?
- The distance between two neighboring pegs counts as 1 unit. Area comes from the corners of the shape, and perimeter adds the length of each side, so a slanted side across a square counts as about 1.41 units.
- What can students explore with a geoboard?
- Area and perimeter, shapes with the same area but different perimeters, the properties of triangles and quadrilaterals, symmetry, slope on the grid and fractions of a square. Print the board to record a shape on paper.
More classroom tools
Whole numbers, fractions, decimals and negatives. Mark points and draw jumps for adding and subtracting.
Hundreds ChartGrades K to 3Color squares, hide numbers to fill in, and light up skip counting by any number.
Place Value ChartGrades 1 to 6Type a number and see each digit's value, expanded form, word form and base ten blocks.
Ten FrameGrades K to 2One or two frames with two-color counters, for counting, making ten and quick looks.
Multiplication ChartGrades 2 to 5Up to 12 x 12 or 20 x 20. Tap a product to light up its row and column, hide answers to practice, and print.
Fraction StripsGrades 2 to 6A fraction wall from wholes to twelfths. Shade pieces to compare fractions and find equivalent ones.
Number BondsGrades K to 2A whole and its two parts. Build bonds, practice the missing part, and print a worksheet.
Base Ten BlocksGrades K to 5Build any number to 9,999 with ones, rods, flats and cubes. Ten trade up for one, and a block breaks back into ten, to show regrouping.
Graph PaperGrades 1 to 8Printable square grid, dot grid, coordinate axes and isometric dots, in the square size you choose.
Analog ClockGrades K to 3Drag the hands, read the time in digits and words, and practice with random times from the hour to the minute.
Pattern BlocksGrades K to 5The six classic blocks to drag and turn: make pictures and patterns, tile shapes and explore fractions of a hexagon.
Algebra TilesGrades 6 to 9Build expressions from x squared, x and 1 tiles, flip them negative, and use them to combine terms, multiply and factor.
Coordinate PlaneGrades 5 to 8One or four quadrants. Tap to plot points, join them into shapes, and print blank grids.