7th Grade Life Science Curriculum Unit 1: Introduction to Scientific Methods Lesson #7: Mealworm Experiment Objectives: After completing the lesson, students will be able to: Develop a meaningful question about mealworms (based upon observations) Perform an investigation based on that question and present results. Key Question: What types of questions can we answer by an experiment? How do we write an accurate procedure? How can we record, organize data accurately and share it with others? Overview: Day 1: Students observe mealworms and develop experimental questions. Day 2: Students discuss and select ONE question to investigate. Students up the experiment form/procedure. Day 3: Students ALL do the SAME selected mealworm investigation. Day 4: Students discuss their results and write up a lab report Time Required: 4 50-minute class sessions Materials: One Mealworm (Tenbrio larvae) per student One Pert dish with cover per student Oat bran Raw potato pieces Private Eye Loupes or Magnifying glasses Large strips of paper/Markers Alternate food (or supplies for student experiment) Procedure: Day One: 1. Discuss laboratory expectations and safety. Show how to handle mealworms. 2. Pass out one mealworm in a covered Petri dish (without bran or potato)/ student 3. Have each student use Private Eye Loupe, ruler, and color pencils to record observations in his/her journal or on a piece of paper. Observations could include shape, size, number of legs & segments, color drawing, analogies, movements, response to stimulus etc. 4. If you have time, add a bit of raw potato and or bran and have students continue recording observations with these new items. **NOTE: Collect the mealworms at this time or they will be a distraction during discussion time. 5. Either have students share their observations within their groups or as a class. 6. On the same observation sheet, have students brainstorm 2 to 3 questions they have mealworms (students usually asked questions either based upon their observations such as: What would happen if you put two meals worms together? Do they have eyes or their curiosity: What would happen if you cut the mealworm in half? How do they mate?). 7. Students share their questions (either in their lab groups or as a class). Write down 10-12 student generated questions then discuss what makes a questions appropriate/feasible for a a laboratory investigation (the mealworm is not hurt, we get some useful information from our research, we have the laboratory equipment, etc.). Below are student questions that experiments can be designed from: *What is the average length of a mealworm? *Do mealworms prefer dampness or dryness? *Do mealworms prefer light to dark? *Are mealworms attracted to cold or warmth? *What foods do mealworms like to eat? (this one is the easiest to do) 8. Explain to the class that in the scientific community only a few experiments are funded and for this class, only ONE question/experiment can be done.(Reassure students for this particular experiment we only have one period to do the actual experiment; but other experiments during the year will take more than one period). Try to have students narrow their selection to the top three experiment questions. Have the class vote/discuss which of their questions they would like to answer by doing an experiment. As the teacher you have the right to veto their choice. 9. Before Day Two, collect the laboratory materials and supplies needed to do the experiment. For example, if "What foods to mealworms like to eat?" is your question, bring in food, plate-like container to model the experiment on Day Two and for the students to do on Day Three. Day Two: 1. As a class set up the experiment. Decide beforehand what you want the students' experiment write-up to look like/include. Design a simple rubric to help students understand how their written work will be assessed. You may want to include the initial mealworm observations. 2. Have students write out the experiment that will be done the next day. Pay special attention to how students write the procedure and make the data chart. Students can always word-process or copy this first draft as homework. *NOTE: students who miss Day Two can copy classmates' lab write-up on Day Three. Day Three: 1. Discuss laboratory expectations and safety. Show how to handle mealworms. 2. Pass out one mealworm in a covered Petri dish (without bran or potato)/ student 3. Have each student use Private Eye Loupe, ruler, and color pencils to record observations in the data section of their lab write up. 4. If your experiment uses more than one mealworm/students have students exchange their mealworms with each other keeping them in the same Pert dish (numbers on the Petri dishes would me helpful) **NOTE: Collect the mealworms at this time or they will be a distraction during discussion time. 5. Either have students share their observations and data within their groups or as a class. If lab write up includes class data charts, collect this information at the end of Day Three or the start of Day Four. Day Four: 1. Have students take out their copies of their lab write-up. 2. Discuss each section of the lab write-up using the rubric you have decided. Pay special attention to the data collected and what it means. Discussions can include whether students' hypotheses were correct/incorrect, possible sources of human errors, suggestions for next time and finally what did they learn from their experiment. 3. The rest of the period could be used for students to finish their Lab Report to insure every student turns something in (versus assigning finishing the lab report as homework which is an option as well). Assessments: 1. Student Lab Report of their Mealworm Experiment 2. Alternative Assessments could include a drawings of the experiment or oral reports 3. Give students a potential experimental question, have them write-up a Lab Report: Problem, Hypothesis, Materials, Procedure, and Data Chart (without data). Homework: DAY ONE H.W.: Students write out the experimental question and one hypothesis. DAY TWO & THREE H.W.: Students write or word-process second draft of write-up DAY FOUR: (Optional) Students finish their Mealworm Lab Report or do Assessment #3 OUSD Science Content Standards (State of California Science Content Standards): Investigation and Experimentation 7.7a, 7.7c, 7.7e References: Prentice Hall: Science Explorer Focus on Life Science Conducting a Scientific Investigation p. 762-763 Chapter 13: Mealworm Project p. 397,411,417,426, 429 Mealworm Caresheet Things to Do with Live Insects Notes: Vocabulary Words: Experiment Investigation Observation Hypothesis (Hypotheses pl.) Procedure Data Conclusion Insect Mealworm Metamorphosis Back to Life Science Unit 1 Contents