Lichen Hunt--Identifying and Classifying Lichens by their Physical Characteristics

This activity is designed for students to explore the nature around them. They will also learn how to categorize their lichen according to physical characteristics. Finally, they will learn to recognize lichens in categories other than their own. By doing this activity, students are required to think critically because they will need to think about the lichen's physical characteristics in order to classify it into a group. Other skills developed by this activity are observation, drawing, making inferences, and oral presentation.
One concept of this activity that the students will understand is that there are three categories of lichens.
Another concept the students will learn is that lichens can live after you remove them from the forest.
Finally, the students will learn that lichens can live through all four seasons and they normally grow during the fall and spring.
Vocabulary Words: lichen, crustiose, foliose, fruticose

This activity is designed for 4th grade. My class usually has about 20 kids. We are a rural school so we have access to our own nature trail for this activity. If you don't have a forest near you, this activity could be more difficult to do. The lesson would take about an hour, but you could shorten it if you need to. It would include a little bit of lecture and note-taking, but mostly it's a guided discovery lesson. Half of the lesson will take place outside in the woods with the other half being in the classroom. There are no skills or concepts that need to be learned before doing this lesson. I would teach this activity along with a unit I do on classification of plants and animals. The students would be working alone but I would be there to guide them. This activity would be difficult to adapt to other settings because you need woods (or trees and grass) in order to find lichens.

I would introduce this lesson by finding out what the kids know about lichens. I'm sure a lot of kids haven't heard of lichens before. Hopefully they won't know a lot about lichens so they can discover lichens on their own in the woods. The only materials that will be required will be a notebook (to write definitions in), a nature journal, and a pencil. After I find out what the kids know about lichens, I will tell them what a lichen is. I will describe it and tell them where lichens are found, what their use is, etc. I don't want to show them a picture because I want to see if they can find one on their own in the woods. Then I will take the kids into the woods. (They will know all the rules of the nature trail.) Once they think they found a lichen, I can confirm if it is or not. Once they find one, they need to draw it in their journals along with 3-5 words describing it. Next we will go back inside and talk about the lichens that we found. Were they leafy or flat? Did it stick up? At this time, the kids will be able to show their drawings to the class if they wish. Then we will generically categorize their lichens based on leafy, flat, etc. Next I will introduce the three categories of lichens: crustiose, foliose, and fruticose. They will write these definitions in their notebook. I would also have a field guide handy so the kids can see different examples. Finally, on the front table I will have the three different groups and the kids will need to come up and put their lichen in the group they think it belongs in. Did they have it in the right group to begin with? To wrap up the lesson, we will look at each group to see if they classified their lichen correctly and why.

One concern I might have is the kids' behavior out in the woods. You would obviously go over rules for in the woods, safety, etc. before doing this lesson. You might want to somehow "confine" them to an area where you can still see them. If a student is having trouble finding a lichen, they can ask another student for help. This activity is different from other ones I've done with classifying because they won't know what a lichen is so that's a learning concept in itself. Also, the kids are outside exploring "by themselves" without help from me.

For an assessment, I might have the students turn in their notebooks so I know they wrote down the definitions. Also as a follow up assessment, I would have the students go home and find a lichen somewhere outside. It could be in their own yard, woods, anywhere. They can have mom or dad help them if they want. They will need to bring in a lichen and put it in the correct category. My students will have access to woods so ALL students will be able to do this. However, I might give them a couple days to complete it.

4.I.B.2: collect, organize, analyze and present data from a controlled experiment.
4.IV.B.1. Classify plants and animals according to their physical characteristics.