I will give a few examples but the insects that can be designed from leaves, sticks and seeds are only limited by the imagination. Use straight sticks, 3-4 inches long, and 4 maple seeds. Very small seeds or beads can be glued on one end of the stick for eyes. The bottom half of the acorn is the abdomen and the top half or 'hat' is the thorax. Glue a small seed to the top of the 'hat' for the head.
Many beetles have beautiful colors and patterns in nature.
Glue two leaves of equal size to a straight stick of a length equal to or shorter than the length of the leaves. Leaf petioles can be glued on for antennae. The wings can be glued on flat or at an angle to each other. Caterpillars Use straight or wiggly sticks. Paint in outrageous colors.