How Things Work

Explore along with your students, and in the process, you will discover what they know about the world that lies within the garden, how they use their senses to observe, and how they work with others. 

Your class garden, whether it consists of two small planter boxes or covers half an acre, can provide a living laboratory for the study of science. This unit introduces the garden as a structure with many different parts and as a habitat for many living things. The concept of a habitat offers students a meaningful context for their explora­tions throughout the year. All plants and animals, including hu­mans, need a habitat, a place where their basic needs for food and shelter are met. As students investigate the garden habitat, they will learn how factors from temperature to precipitation to soil type affect what can live there. In the next six units, your students will examine various parts of the garden-seeds, soil, climate, tools, plants, and garden animals. The year culminates in a unit that focuses on exploring how these parts of the garden function together as a habitat for many living things. 

Because this unit emphasizes sensory awareness and cooperative skills, many of these introductory activities focus on careful obser­vation, detailed description, communication, and cooperation. The more skilled your students are in gathering information through their senses, the greater their success in hypothesizing and problem solving. Cooperation facilitates class management and enhances learning as students share observations and analyses. You may wish to reinforce these skills by repeating some of these introduc­tory lessons throughout the year. 

Inspire a sense of garden ownership by involving students in the garden-harvesting the last tomatoes (if there is a garden left from last year), clearing weeds, digging a new bed, or even planting radishes in a window box. The In the Garden sections, included in many lessons, suggest ideas for getting your garden started and maintaining it. Refer also to the garden resource book, Gardening Know-How for the ’90s, which will answer your questions and expand your knowledge of basic gardening techniques. 

2- Song: “Take the Time to Wonder”

3- Introduction 

4- Student Goals 

5- Activity Chart 

6- Unit Planner 

7- Recommended Literature 

8- Parent Letter 

9- Garden Explorers (exploring the garden with the senses)

13- Musical Monarchs (cooperative learning)

16- Guessing Garden (cooperative learning; recording skills) 

19- Mystery Plants (sorting; decision-making.)

22- Observation Circles (observation and recording skills)

25- Look Again Trail (observation and recording skills)

28- Garden Tools

32- Scavenger Hunt (observation; cooperative learning)

35- Assessment Checklist

A seed is a promise of a full-grown plant, a small suitcase with a great memory, a package of concentrated energy, a mysterious object waiting for the right conditions to develop. For students, seeds are objects of wonder that they can collect, dissect, and investigate. Some students may still believe that plants are not alive because they do not move. As these children plant seeds and watch them grow, they begin to refine their understanding not only of seeds but also of the characteristics of living things. 

The exploration of seeds is an excellent introduction to this year’s science theme: structure-function. By gathering, examining, and germinating seeds, your students discover how the structure of a seed is related to its function-the creation of new plants. They explore, too, the structure of each part of the seed and investigate its function. They discover how each of these parts relates to the way a seed grows into a plant. They also observe how the external parts of the seed protect the embryo and aid in the dispersal of the seed. And they discover that the embryo itself contains everything needed for a new plant to develop. 

The first unit emphasized observation skills. Now students apply these skills to the Guess-Test-Tell process, a simplified version of the scientific method. Students learn to base their hypotheses on observation and other concrete experiences. Two of the most con­crete experiences students can have with seeds are collecting and planting them. You will find a variety of fall gardening ideas in the In the Garden sections of this unit.

38- Song: “Roots, Stems, Leaves” 

39- Introduction 

40- Student Goals 

41- Activity Chart 

42- Unit Planner

43- Recommended Literature 

44- Parent Letter 

45- Seed Hunt (seed collecting)

49- Seed Detectives (examining seeds)

52- Shoots and Roots (germinating seeds)

56- Hitchhiker Seeds (seed dispersal)

60- The Life of a Seed (planting seeds; story writing)

63- Assessment Checklist 

In this unit, students dig and discover. They dig up a spadeful of soil and discover a dynamic mixture of living, once-living, and nonliving things. As they explore that spadeful of soil and compare it to soil from other places, they deepen their understanding of what is alive and what is not alive. They also investigate an aspect of this year’s theme. Students learn that the structure of the soil functions as a key factor in the lives of plants and animals living in it. They are all parts of a tightly linked system. A change in the soil moisture and temperature affects plants and animals, and as plants and animals live and die in the soil, they alter the soil’s structure. 

The unit builds on knowledge and skills students developed in earlier units. The first unit stressed observation and cooperative skills. The second introduced students to a simplified version of the scientific method, the Guess-Test-Tell process, as a way of investi­gating seeds. Now students apply those skills and their knowledge of seeds to their study of soil. Working in small groups, they explore the physical properties of a soil in great depth as they prepare for an activity staged as The Great Soil Conference, convened by an invited guest playing the role of the Great Gardener. At the confer­ence, students share their insights and discoveries. The conference also provides students with a way of summarizing what they have learned. In the last activity, they apply what they have learned to a real problem in the garden. These two activities assess in very different ways what students have learned. 

The unit itself is organized around preparations for The Great Soil Conference. Students receive letters from the Great Gardener, encouraging them to experiment and explore. Be sure that students save the results of these investigations in a special folder, so that they will be ready to show the Great Gardener what they have learned. The Great Soil Conference is a structured yet motivating way to introduce students to the mechanics of reports and presen­tations. It can serve as a useful model for sharing other investiga­tions, both guided and independent. 

66- Song: “Decomposition” 

67- Introduction 

68- Student Goals

69- Activity Chart 

70- Unit Planner

71- Recommended Literature 

72- Parent Letter

73- All Sorts of Soils (collecting and examining soil)

77- Which Soil Do Plants Prefer? (experiment with soil and seeds)

88- Soil for the Senses (investigating the properties of soil)

84- Mudshakes (investigating the components of soil)

88- Earthworms’ EarthStories (experiments with earthworms and soil) 

92- Does It Hold Water? (testings soil absorbency)

96- The Great Soil Conference (group presentations about soil)

100- Back to the Garden (creating plans to improve gardens soil)

104- Assessment Checklist

Everyone, including each of your students, has an opinion about the weather. It is an important part of our lives. Students know that it affects the way they dress and the activities they plan. In this unit, they discover that it also affects the kinds of gardens they plant and even when they plant them. By analyzing weather conditions and exploring their impact on the garden, students are introduced to the concept of climate. Students discover that although their weather may change quickly-in some places, from hour to hour-the climate changes very, very slowly. Climate is the usual weather that a particular region experiences during the year. The concept of climate takes into account seasonal changes and the average daily weather over a period of 30 years or more. Therefore, even though we may get a record snowfall in October or experience an unusually early spring, neither affects what we think of as the climate, unless such unusual events become the norm by repeating themselves over a very long period of time. 

This unit builds on concepts and skills developed in earlier units. For example, in the last unit students explored how soil affects the garden. Now they discover that climate also makes a difference in determining what can grow in the garden, and when. 

The unit also builds on skills introduced in earlier units. Students continue to apply the Guess-Test-Tell method as they record weather data. There are also many opportunities for cooperative learning. Throughout the unit, the emphasis is on observing, questioning, and testing ideas rather than on rote learning. A hands-on approach to science results in a deeper understanding of concepts and fosters the kind of approach to problem-solving that can last a lifetime.

108- Song: “River Song”

109- Introduction

110- Student Goals 

111- Activity Chart 

112- Unit Planner 

113- Recommended Literature 

114- Parent Letter 

115- What’s the Weather? (exploration of local weather)

118- Tools for Watching Weather (recording data from weather instruments)

122- Weather Watchers (recording weather data) 

126- I Remember When … (interviewing adults about climate)

130- Under the Weather(investigating effects of weather on plants) 

134- When Will Our Garden Grow? (creating planting guide)

137- Weather Report (creating weather reports) 

141- Assessment Checklist 

The new gardening year offers a wonderful opportunity to explore simple machines. With spring coming, many garden tasks are waiting to be done, and each provides an opportunity to explore first-hand how machines help get work done. Whether The Machine is a student’s body yanking on a weed, or a shovel being used to move compost, the parts of each simple machine can be identified. By constructing their own machines, students can experiment with changing how the parts are arranged and experience how their changes affect the tool’s function. These hands-on explorations will help students integrate abstractions like “effort,” “load,” and “ful­crum” into their everyday experience. 

Tools are instruments of change. By allowing us to do more work with less effort, they alter cultures, history, and the environment. The refinement of the digging stick into a scratch plow drawn by oxen sparked ancient Egypt’s civilization. Likewise, new metal plowshares broke the prairie soil of the North American Great Plains and doomed the Native American buffalo cultures, as well as the prairie ecosystem itself. In nineteenth-century America, tools were a farm family’s livelihood. Farmers were adept at devising and repairing tools and adapting parts. As cast-iron plows replaced wood in the early nineteenth century, some farmers simply re­placed their wooden cutting edges with saw blades. Encourage students to think of their own innovations for tools as they use them in the spring garden. 

Garden tools are always in short supply. Take advantage of the neces­sity to reinforce cooperative skills like sharing tools, waiting one’s turn, and taking responsibility. Review tool-safety rules often. Encourage students to work together and share their experiences with each other as they explore how simple machines work. 

145- Introduction 

146- Student Goals

147- Activity Chart

148- Unit Planner

149- Recommended Literature 

150- Parent Letter

151- Move It! (Any Way You Can) (exploring force using tools)

155- Seesaw Ups and Downs (experimenting with levers)

159- Playground Machines (experimenting with force and simple machines)

162- Ramp Romp (investigating inclined planes)

166- Garden Levers (investigating tools used as levers)

169- Weed Machines (investigating force and levers)

172- Invent a Tool (inventing a new garden tool)

176- Assessment Checklist

In this unit, students conduct a variety of investigations to explore how different plant parts function to ensure the survival of the whole plant. Even though the plant world is extremely diverse, almost all flowering plants including the tall redwood tree, the marsh-loving cattail, and the saguaro cactus-have certain com­mon features (roots, stems, and leaves) and common characteristics (roots grow downward into the soil and stems and leaves grow toward sunlight). 

The structure of a plant functions to meet its basic needs for water, sunlight, air, and nutrients. The lessons in this unit start by explor­ing students’ understanding of these plant needs and their knowl­edge of plant parts. In assessing what students know, and in giving them opportunities to observe plant parts and plant needs, you will help them establish a meaningful context for the experiments on root, stem, and leaf growth. Thus, when they express amazement at a plant bending and twisting through a maze to reach light, they will also understand that the plant needs light in order to survive. 

Throughout the year students have had opportunities to set up and monitor experiments. This unit continues to build on their experi­ence and suggests that students practice setting up and monitoring experiments independently. In the beginning of the unit, the class will build individual root view boxes from milk containers. Each student should construct and plant at least one. These boxes will be used in most of the experiments, and will give students an uncom­mon opportunity to observe a growing plant both above and below ground.

180- Song: “Roots, Stems, Leaves” 

181- Introduction 

182- Student Goals 

183- Activity Chart 

184- Unit Planner 

185- Recommended Literature 

186- Parent Letter 

187- What’s a Plant? (drawing plants; identifying characteristics of plants) 

191- A Root View (experiment on roots) 

196- Dissect a Plant (comparing edible and non-edible plant parts)

200- Sun Blockers ( covering plant leaves to discover plants’ need for light) 

204- Watercolors (stem experiment with colored water)

207- Which Way Is Up? (root experiment)

210- Rooting for Water (experiment comparing watered and unwatered roots)

214- Amazing Plants (experiments with bean plants and light)

218- Get a Grip (experiment with peas)

222- Plant and Tell (garden plant scavenger hunt and group reports)

225- Assessment Checklist 

Every day, small garden animals routinely busy themselves with an amazing set of behaviors. These animals’ structures — legs, eyes, antennae — permit the animals to get the food and water they need, protect themselves, and find shelter. Consider the click beetle, whose hinged body is designed so it can flip itself over when it becomes upended. In the ant world, different species harvest and store seeds, kidnap and enslave the larvae of other species, and herd and milk aphids. Snails and slugs secrete their own slimy pathways to help them glide along.  A one-acre plot of land can host over a million insects with their fascinating and varied behaviors.

This unit’s investigation of small garden animals will provide a chance to study these creatures and discover how all of them, different as they are, manage to survive. As students search for and watch animals in their habitats, draw them, and investigate how they touch, eat, move, make sound, and defend themselves, they will be learning how the animals’ structures serve them. This study integrates physical science through investigating the sounds animals make, the structures they use to eat, and the ways they move. The first three lessons involve students in capturing small garden animals and observing them in the classroom. By the end of the unit, students will have a foundation for understanding how an animal survives in its habitat.

228- Song: “No Bones Within”

229- Introduction 

230- Student Goals

231- Activity Chart 

232- Unit Planner 

233- Recommended Literature 

234- Parent Letter

235- What’s in Our Garden? (exploration of garden animals)

239- Sense Abilities (investigating animal senses)

242- On the Move (mapping animal movements)

247- Better to Eat You With (investigating animal mouth part functions) 

250- Safety First! (investigating animal defenses)

253- Sound Ideas (investigating sound) 

256- Animal Flashes (matching animal parts and functions)

259- Assessment Checklist