Create a three dimensional model of a cell by using clay. Alternatively, use recyclable materials, such as a shoe box. Fill the box with cellophane or cotton balls to make the cytoplasm. Then place bottle caps, marbles, pipe cleaners and buttons to make the organelles. You could use a jar's lid to make the nucleus. You could also make a cell model inside of a plastic bag full of hair gel, to represent the cytoplasm. Use beads of different colors and shapes to represent the organelles.
Craft a respiratory system using balloons, two drinking straws and a large plastic bottle. Attach two small empty balloons around an end of each drinking straw, without blocking the air passage. Cut off the bottom of the plastic bottle and make two holes on the cap. Place the balloons inside the bottle and pass the straw through the cap's holes. Close the bottom of the bottle by cutting a large balloon and wrapping it around the rim.
Children can learn the differences between invertebrate animals, such as insects, spiders and crabs, by creating them with egg cartons, construction paper and pipe cleaners. Use the egg cartons to make the bodies and the pipe cleaners to make the legs. Make antennae and insect wings with construction paper. Before you start crafting, show illustrations and discuss with the children why these animals are different. The number of legs is a fundamental difference between these invertebrates: six for insects, eight for spiders and ten for crabs.
Make a three-dimensional tree using cardboard boxes and rolls. You could use cereal boxes for the trunk and cut cardboard strips for the branches and roots, or you could use glued toilet paper rolls. Use the cups of egg cartons to make the fruit. Draw and cut out leaves and flowers, and do not forget to paint them with vibrant colors. Alternatively, draw a tree on a large piece of cardboard and use leftover fabric to cover it, observing the right colors and labeling each part.