Growing plants has been a favourite topic in primary science for a long time but how much learning goes beyond the ubiquitous pots of cress seedlings lined up on the windowsill? Research has shown that primary pupils know far less about plants than animals and that their knowledge about growth is limited.
Children should know more about plants - after all without them none of us would be here. Humans have depended on them throughout our evolution. We wash and preen ourselves with plant products, feed on them, wear them, travel on them, use them when we are ill, and send them to mark the event of death. Plants are big business. The challenge to produce more food at lower cost has spawned a whole batch of new plant technologies - some of which, such as genetic modification of crops, are controversial.
In the age of the television makeover, plants are stars. Gardening programmes are hugely popular and their presenters attract cult status. Garden centres and supermarkets overflow with a bewildering range of plant produce to grow, nurture and eat. These products provide an increasingly rich resource for teachers and help link plant work with the real world.
Plants provide a relatively cheap and reliable test-bed for investigating a range of living processes. In the past few years "fast plants" have been developed for use in schools. These are cabbage-like plants that complete their life cycle from seed to seed in about 35 days. Because the life cycle is so fast, they are excellent for helping children study germination and growth, take measurements and record significant events such as flowering, pollination and appearance of the first seed pods. The plants are grown on capillary matting so that water is assured and they are placed under a bank of fluorescent light tubes so they get permanent light. When flowers start appearing (at about 15 days) they need pollinating and, in the absence of bees, children do this. It helps if they make a buzzing noise as they transfer pollen from one flower to another because botanists have found that sound vibrations help pollen detach from anthers.
"Fast plant" technology is supported by an organisation called Science and Plants for Schools (SAPS). It runs training courses on using the resource and may be able to give your school a grant towards the cost of building a light bank. If you sign up with SAPS you also get an excellent newsletter called Osmosis containing ideas for classroom experiments.
Plant work can be creative. Wall displays of children's paintings of flowers, fruits and vegetables help them link observational work in science with art. Poems can help children to express the seasonal changes they see and to reinforce concepts about the variety of plant types and flowers. An activity children enjoy is to grow a grasshead. These are attractive and can be kept in the classroom or taken home; just ask the children to give the grassheads a haircut every now and then - or should that be a grasscut or even a mow?
Teachers are increasingly looking for ways to balance science work with the demands of numeracy, literacy and ICT. The variety of work that is possible with plants and the measurements and data that this can yield means that plant science in the primary curriculum should continue to grow. Healthy growth, however, requires careful nurturing to sustain it. This should come from an increase in the diversity and depth of work that is done in schol using this fascinating learning resource.
Making a grasshead Cut the foot off an old pair of tights. Put a pinch of grass seed and a spoonful of compost into the toe and then stuff water-absorbent material into the foot to make a grasshead. Tie off the open end and soak the grasshead in water. Decorate your grasshead to make a face. Keep the ball moist at all times.
How long did it take your grasshead to grow "hair"? What happens to the hair if you put your grasshead in a cupboard? Will the hair grow if it is cut?
Linking plant work with literacy objectives:
* Give children six words about germination and growth and ask them to arrange them alphabetically. Ask children to fold an A4 landscape sheet of paper three times and enter each word and its letter with a simple explanation of the word into each section (Year 2).
* Use a concept map where words on cards such as seed, root, shoot, soil, water, warmth, sun and grow can be joined by other words to make sentences such as: A seed needs warmth to grow (Year 2).
* Encourage children to write about their investigations on conditions for seed growth using a variety of openers, for example: We were trying to find out if ... The best conditions to germinate a seed were ... We could tell because ... (Year 34).
* Get children to write a sequence of instructions and see if another group can follow them, for example: How to make a grasshead. Children could also design a plant-care label using symbols and instructions to describe the plant's needs (Year 56).
* Give children gardening books and seed packets to find out about ways in which different seeds should be planted. They could make a planting calendar for flowers and vegetables based on information from books (non-fiction work at key stage 2).
Linking plant work with numeracy objectives:
* Open up seed pods and count the seeds up to 10 or 20 (receptionYear 1).
* Say whether there are enough or too many seeds to plant in a pot (Year 2).
* Sort fruits or seeds into different shapes and developing mathematical vocabulary, for example: round, long, thin, curved (Year 2).
* Devise a tally system to record seeds in pods and fruits containing large numbers of seeds. Encourage children to use conventions such as . LESS THAN LESS THAN and
to compare numbers of seeds in different fruits (Year 4).
* Record the heights of growing plants and work out growth rate in centimetres or millimetres each day (Year 5).
* Identify the period of most rapid growth of a seedling from a line graph (Year 6).
* Type labels for each part of the germination process from a word bank and use in literacy links activities (KS1).
* Take photographs with a digital camera of different stages of growth and paste these into a word processed account or story about germination (KS12).
* Dvise questions about seeds and germination, for example: Which is the world's largest seed? Post questions via e-mail to a science expert - try: www.ajkids.com (KS2).
* Enter results of growth measurements for each day on to a spreadsheet and select a graph to show changes in patterns of growth - children should select a line graph for this (KS2).
Martin Braund is senior lecturer in science education at Bretton Hall college, University of Leeds, and the author of a handbook on plant science for primary schools to be published in September.SAPS, Homerton College, Cambridge CB2 2PH. Tel: 01223 507168. www-saps.plantsci.cam.ac.uk.