Finger painting demonstrates symmetry when children paint only on one side of an evenly folded sheet of paper. When the painted side presses onto the unpainted side, that side becomes imprinted with a replicated reflection of the original painting, clearly showing the crease as the line of symmetry -- the division between both equal halves or proportions. This activity works well if children paint half of a butterfly, a face or a shape such as a heart or square.
Photographs of natural symmetry -- such as snowflakes, butterflies or ladybugs with visible lines of symmetry -- reenforce the idea of the reflection property. Comparing symmetrical and asymmetrical images also improves a child's ability to discern between these images. Once children start to understand what is and what isn't symmetrical, group activities will help them learn from each other. Teachers can show students sets of photos, asking them if they are symmetrical, before drawing the line of symmetry on each photo.
Appealing to a child's stomach also retains his attention. This edible lesson starts by showing the children an orange, with the teacher demonstrating that any way the fruit is sliced down the middle, both halves remain the same size. Large trays with fruit, cookie or candy arranged in a symmetrical manner can help reenforce the concept of symmetry before each student receives a treat from the tray.
A symmetrical word game requires a group of students, divided into teams, with one sheet of paper and pen per team. Under the pressure of a timer, students must write down as many symmetrical words -- such as "DEED," "TOOT" or "MOM" -- as they can before time runs out.
A symmetrical block game, played in pairs, has students move their desks together and use the division of the desks as a line of symmetry. Using a set of blocks, one child creates a unique formation that the other child tries to mimic.