To begin this lesson, I call the kids one table at a time to sit on the floor. Once everyone is seated, I explain to them that we are going to go on a little "field trip." The goal for them is to look carefully at the roots and leaves of plants found in our desert landscape and take note of their unique qualities.
I call one team at a time to line up at the door to take a nature walk around our campus. I tell the kids that we are going to stay together and gather around a few trees and plants to discuss the traits of dessert plants in our area.
The first desert plant we look at is a creosote bush. I ask the kids to quietly look at it for a minute and think about its attributes. After a minute or so, I ask the kids to raise their hand to share something they notice about the plant. The first student I call on tells the class that she notices that the roots are showing. The next student states that the flowers and leaves of the plant are very small.
I then pose this question:
Why do you think the roots are showing and the flowers and leaves are small?
I give the kids about 30 seconds to think about it and then call on a few volunteers to share their ideas. After about 4 kids share, one has built on what he's heard from the others and says, "I think it's because it's hot and it doesn't get very much water." Another student tells the class, "If the leaves and flowers were big, it would need more water to live." Wow! these kids are thinking like scientists!
We continue the rest of our exploration in the same fashion. We visit two more plants, if time allows. I stick to the 10 minute time limit so we can complete the lesson on time. If the discussion here is rich, I will take time from another section to accommodate the discussion.
Upon returning from the nature walk, I have the kids sit on the floor for a discussion about what we noticed.
I take out a piece of chart paper and label it "Desert Habitats." I ask the kids to recall the things we talked about on our nature walk.
As the kids share out what they remember, I record it on the chart. I then ask them if they can think of any animals that live in the desert and I list them as well.
As I list the animals, I ask them why the desert is a good habitat for each animal and see if they can come up with any ideas based on what they know about each one.
I do this because I want the kids to start making connections across science content. We've learned about some animals and animal life cycles. Since we live in the desert and are familiar with desert animals, this is a great topic/lesson to begin this type of connecting.
I call on random volunteers to share their thoughts. There are no wrong answers because they are theorizing and any misconceptions will be ironed out by the end of the lesson.
For this step in the lesson, I have the kids remain on the floor. I refer to the beginning of the list they created on chart paper. I ask them how the desert plants are helpful to the animals and ask them to make connections between the plant characteristics and the needs of the animals.
As we have this discussion, I begin to share and explain to the kids about certain animal adaptations such as jackrabbits having unusually large ears so they can keep cool. I also talk about how the javelina can eat prickly pear and saguaro without injuring their mouths because that's how they take in water since there is none in the desert. I elicit ideas by calling on random volunteers since this is a challenging concept for the kids.
The goal is to have them provide the initial idea and the I fill in the missing pieces or the needed additions. This section should not take too long because the hard work was done in the previous section.
To evaluate the learning in this lesson, I have the kids complete TWO tasks:
The idea here is for the kids to show that they have learned the necessity for desert plants to have shallow roots, small leaves and small flowers, if any at all. It is also for them to show how the animals rely on the plants in the desert to provide for their needs.
As the kids work, I roam the room to observe work progress, ask students questions and clarify misconceptions.
Some question I might ask are:
I ask a variety of how and why questions because the require explanation rather than simple yes and no answers. If a student struggles, I help by guiding their thinking and then having them repeat the answer again on their own.
When everyone is finished with their work, we meet back on the floor to share our work with our floor partners. Once we share with our floor partners, I call on 3 random students to share their work with the class and explain what they did and why. I call on the random students by pulling name sticks from a name stick can. Each person chosen sits in the teacher chair to present.
A quick extension to this lesson is to ask the kids to think about what they could use in the desert to sustain themselves if they should find themselves stuck out there.
I use this as the extension for two reasons:
I leave them with a request to talk to their parents about what they learned in science today so they can have a discussion about desert survival.