Gr 4 and 5 children from Blossom Road and Dennegeur Primary Schools participated in a practical lesson at Edith Stephens Nature Reserve where they found out about grasshoppers. These lessons are offered to teachers who have attended in-service teacher training courses presented by the Primary Science Programme (PSP). The Hands -on- Environment-Programme aims to model practical lessons that teachers can easily and realistically incorporate into their busy schedules.
Understanding a basic life cycle
The life cycle of all organisms follows a similar pattern: male and female mate to produce a fertilised egg which then is born or hatches into a new young individual. The young grow and develop into an adult that can reproduce and starts the cycle all over again. What varies is the time it takes for a life cycle to be completed and of course the different stages in a life cycle that an animal or plant passes through to become an adult.
The children worked together to place pictures of the different stages of humans, cats and a tomato plant in the correct order.
The next challenge was to try and work out the life cycle of a grasshopper. The male and female part was not so difficult but what happens then?
Once the groups had spent some time illustrating what they thought happened, I explained that the female lays eggs in the soil and the baby grasshoppers that hatch are called nymphs. Nymphs have very small wings and in order to get bigger have to eat and grow and then split out of their exoskeleton in the process of moulting. This happens about 5 times before the wings are big enough for the adult to fly properly and find a mate.
The grasshopper Game
To consolidate the fact that the body of a grasshopper has three parts and consists of a head, a thorax and an abdomen we played a game with dice. The groups had to throw numbers to get the different parts of the body. The thorax is a 3, head a 4 and abdomen a 6 and then you have to get six 2’s for the six legs and two 1’s for the feelers and 5’s for the eyes. The excitement rose to a crescendo as the dice were frantically cast to construct a grasshopper. Great fun.
After break,children spent a very happy half hour catching grasshoppers. They are very fast and manage to elude all but the best hunters.
Back in the classroom, everybody was challenged to ‘interview’ a grasshopper to think about how a grasshopper lives and survives. Mini microscopes were constructed with a 10x magnification hand lens and petri dish. The children were able to get a really close look at a grasshopper and to draw it.
The big microscope
Right at the end of the lesson, the children were rewarded for all their hard work and were shown how the dissecting microscope works.
They were fascinated to see that a grasshopper has 2 big compound eyes and 3 very small ones. No wonder it is so hard to catch them! We looked at the different parts of the body and even dissected the muscle in the strong jumping leg. It looks just like chicken and challenged the kids asking why we don’t eat insects. They found the mouth parts covering the strong black mandibles fascinating and were upset when the poor grasshopper didn’t want to oblige us and eat a piece of grass. I am not sure that I would want to eat anything if I had sharp tweezers being shoved into my mouth!
All animals were safely released back into the wild.
At question time, a hand shot up ‘Miss, when can we come back again?’ indicated to me that they had enjoyed themselves. Thanks Gr 4’s and 5’s for sharing in finding out more about grasshoppers.