Though people rarely have the opportunity to see an authentic igloo, the shape of this temporary snow dwelling is widely recognisable. A model igloo makes a good toy or winter decoration. By building yours from plastic foam, you can imitate the appearance of snow without worrying about losing your igloo to the heat of the sun once spring comes.
Making the igloo
Cut bricks from the polystyrene (plastic foam). Use the electric saw to cut the polystyrene sheets into strips 2.5 cm (1 inch) wide. Cut these strips down into 2.5 cm (1 inch) pieces, forming rectangular bricks. Make at least 50 bricks.
Draw the base of the igloo on the wooden base. Draw a circle with a diameter of 15 cm (6 inches). Attach to this a 7.5 by 7.5 cm (3 by 3 inch) square, facing outward and lined up with the edge of the circle.
Lay down the bottom layer of bricks. Glue bricks to the wooden base in a line to cover the outline you just drew. Lay them down so their long sides are lined up against the outline on the wood.
Create a wire dome frame. Stretch a piece of craft wire from the inside-bottom of the igloo shape on one side to the opposite inner side on the circle, arching the wire to a height of about 12.5 cm (5 inches). Hot glue the wire to the igloo base at the points where it touches the first layer of bricks. Stretch and glue a second, identical piece of wire in the same way, only position this one to cross the first wire at the centre, forming the dome.
Build up the walls and top of the igloo by gluing more bricks. Stagger the bricks for each layer to lay halfway over the previous layer, just like bricks laid in cement for a building. Build the walls to lean on the shape of the wire dome.
As you get closer to the top of the dome, cut a few bricks in half in order to fill up the section at the very top; these may end up laying in a less orderly configuration as you finish covering the wire frame and fill in the rest of the igloo's top, but as long as the dome is covered, it will look right.
Making the tunnel
Let the glue dry to hardness.
Cut out a small, rectangular opening at the base of the igloo with the craft knife at the point where you drew the square in Step 3. Make it about 7.5 cm (3 inches) high and 5 cm (2 inches) wide at the bottom.
Build the small entrance tunnel. Use some of your remaining bricks to build a cube-shaped entrance tunnel around the opening you just made, building from the bottom up. Make the walls, laying them in the same alternating pattern that you used for the dome. Glue one layer of bricks to form the top of the entrance.