1. Define biodiversity.

Tell students that they will explore the diversity of life and prepare for participation in a bioblitz. 

Write the word biodiversity on the board, with “bio” in a different color than “diversity.” Ask students to discuss this word in pairs and generate a definition in their own words (Possible response: “bio” means life, and “diversity” means different; biodiversity means the variety of life on Earth.) Explain that there is a great deal of diversity on Earth, and that diversity is all around them. Ask: Why is biodiversity on Earth important? Refer to the encyclopedic entry for biodiversity in the media carousel for examples of the value of biodiversity for all life.

Project the Biodiversity and BioBlitz presentation, and distribute a Biodiversity By The Numbers worksheet to each student. Have students use a pencil with this activity. 

2. Explore biodiversity and biological classification.

Projecting slide 2, give students an opportunity to guess or estimate the numbers of species on Earth, writing their ideas on the board. Ask: How many species do you think have been identified and given a scientific name? (1.75 million) How many species do scientists estimate there are on Earth? (possibly 7 million). After students share ideas, reveal the scientific estimates on slide 3. Next, students will observe photos of different organisms to determine some of the characteristics, or traits, that make different species unique.

With slides 4, 5, and 6, explain that, even with all this biodiversity in the world, we know that some organisms are more closely related than other organisms. Tell students they are going to play a game of “which one does not belong.” Each slide will include three organisms. Two are closely related, while the third organism is in a different class. Guide students through each slide to see if they can identify the organism that does not belong with the other two. For each slide, elicit explanations from two or more students to the prompts: How could you tell? What characteristics helped you decide? Prompt students to explain the characteristics that may be shared by the two organisms in the same class, which are not shared by the third organism. At the end of the slides, emphasize that special characteristics of organisms allow us to group them into similar types of organisms. 

3. Introduce taxon groups.

On slide 7, introduce or review different taxa (singular: taxon), or groups, of organisms organized in a system called biological classification. Explain that this term refers to the organization of organisms into groups based on their characteristics. Ask: What taxon do snakes, alligators, and turtles belong to? (reptiles) Tell students that reptiles, mammals, amphibians, and birds are all classes of a larger group called vertebrates. Vertebrates, or organisms with a backbone, and invertebrates, or organisms without a backbone, comprise the kingdom Animalia. Plants, fungi, and other kingdoms are organized in similar ways.

Moving to slide 8, show the photo of an organism from a taxon. Prompt students to make observations:

• What are some characteristics you can see that differentiate this organism from others? (Possible response: vertebrate/invertebrate; type of outer layers such as scales, hair/fur, feathers, skin, exoskeleton; appendages and body parts)
• What taxon do you believe this organism belongs to? Point out to students that the names are on the worksheet.

Explain to students that the next slide reveals several defining characteristics of each taxon. Note for students that, while these are common characteristics, there are always exceptions within each taxon. For example, a few mammals lay eggs, and one sea turtle is semi-warm-blooded. Some plants do not contain chlorophyll to make them green, and some fungi are not made of hyphae tubes. So, most members of each taxon will have all of these physical characteristics.

Moving through the slides, have students write or sketch two or three defining characteristics of each taxon. Have them include an example of a local organism from each taxon grouping on their worksheet.

4. Have students estimate biodiversity for various taxa.

Divide students into pairs or small groups of three and have them spend approximately five minutes to estimate the number of species they believe belong within each taxon, by writing the numbers from the Approximate Number of Species box with each taxon. After groups finish, ask a few to share their estimates for each taxon and their reasoning. Reveal the approximate number of species for each taxon. Talk about the numbers, and discuss any surprises they see.

5. Explain that a bioblitz is one way of documenting biodiversity.

Make sure students understand that biodiversity is not a term that is reserved for tropical rainforests. There is incredible diversity from the bottom of the ocean to their backyards, in extreme environments such as the geysers in Yellowstone National Park, and even in urban environments. Explain to students that the class will engage in a bioblitz—a short, intensive study of the biodiversity of an area. Participants will document findings and share what they found through an online observation platform called iNaturalist.org. 

6. Show students the iNaturalist tutorial.

Project the iNaturalist website (the about section), and show students the Observe Nature with iNaturalist video. Browse the map and observations for your local area. Under “Species,” students will see the various taxa groupings on iNaturalist. 

Explain that at their bioblitz, students may have an opportunity to use iNaturalist to record observations using tablets or other mobile devices. They will also work with their team to identify what they see using biological classification, including the taxon groupings from the slideshow. Bioblitz participants also upload and share observations with other bioblitz participants as well as the broader iNaturalist community. 

7. Have students reflect and predict.

Have students spend five minutes responding to the following prompts in writing: 

• Why is biodiversity important?
• What taxa do you expect to find with the most biodiversity in your park? Support your response with information using your worksheet to help you answer this question.
• What part of the bioblitz experience are you wondering about, and why?

Collect students’ written responses as they leave class and keep them for students to refer to after BioBlitz.