MnSTEP Teaching Activity Collection > MnSTEP Activities > Guided Leech Activity and Record Keeping in a Science Notebook

Guided Leech Activity and Record Keeping in a Science Notebook

Kim Toops
Prairie Woods Elementary
New London, MN
Based on activities from the MnSTEP Elementary Inquiry and Assessment Institute
Author Profile


In this classroom activity, students will observe leeches, develop questions about them, and decide as a class which question to investigate further. The teacher and students will create a scientific investigation to test their question. A science notebook will be utilized to record questions, data, and results.

Learning Goals

Learning Goal: The student will understand the nature of scientific investigations and the importance of keeping a notebook.

Concepts and Content:
1. The student will explore the use of science as a tool that can help investigate and answer questions about the environment.
2. The student will ask questions about the natural world that can be investigated scientifically.
3. The student will know that scientists use different kinds of investigations depending on the questions they are trying to answer.
4. The student will participate in a scientific investigation using apporpriate tools.
5. The students will begin utilizing a science notebook to record information.

investigable question

Context for Use

This lesson is designed for third grade students. It will be used at the beginning of the year to introduce the idea of investigative questions and the use of a science notebook. The class completing this activity is comprised of 20 students in a rural school. It is a lab activity that will take about four 45 minute class periods to complete. (Not including the development of a poster to display test results.) Equipment needed: leeches, clear glass dish to observe leeches, science notebooks and depending on the investigative question decided on by the class and teacher, more equipment to test the question. The equipment could include thermometer, stop watch, ice, heat source, construction paper, etc. Students should know how to read a thermometer and possibly measure with a ruler. This activity will occur at the beginning of the year and would be easy to adapt to other grade levels and other settings.

Subject: Biology, Education:Assessment
Resource Type: Activities:Lab Activity, Classroom Activity
Grade Level: Intermediate (3-5)

Description and Teaching Materials

Day 1:
This will be the first science activity of the year. The teacher will pass out the science notebooks and the students will be given a minute to look them over and write their name on the front of the notebook. The teacher will ask the students to suggest ways that scientists would use notebooks like this. One way to utilize the notebook is for observations. The teacher will place a clear glass dish that contains a leech in pond water on an overhead projector and the students will observe the leech. The teacher will model the use of the notebook as the observation begins. Together the students and teacher will develop questions about the leech, draw pictures, and write general comments about the leech.

Day 2:
The teacher and students will revist the questions written the day before. Together they will decide which questions they are most interested in and the teacher will record this on a large piece of paper. They will then look at the questions and decide, with the teacher's help, which question(s) could be tested. A concensus will be reached as to a question to be investigated. The investigative question will be recorded in the science notebooks. The teacher and students will discuss strategies for developing a test and also discuss variables. The testing details will be recorded in the notebook. The teacher will gather appropriate materials for the next session.

Day 3:
Pior to each group of 2 or 3 students being given a leech and materials to test the question, the teacher and students will discuss data that will be important to record and some modeling will occur as to how to do this in the science notebook. Students will run their tests with the teacher circulating to each group and giving tips on recording information.

Day 4:
Teacher and students will look at the results of their investigation and discuss results and record them in the science notebook. Discussion about the investigation and what worked and what didn't will occur. Additional days can be spent on making posters about their results and sharing them with each other or other classes.

Teaching Notes and Tips

Some common areas of confusion might be just what is an investigative question? Because this is the first time the students have been exposed to an inquiry activity, a discussion is needed about variables and how just one variable at a time should be changed in the investigation. The students should be told to not handle the leeches, but if one does attach to a student, a small amount of salt at the site of the attachment will make the leech fall off the skin. This activity is completely different from what my students and I have done in the past because we have never decided our own testable question. We've just done activities as they have been set up in our curriculum.


The students will achieve the learning goal of understanding the nature of a scientific investigation. During discussion about the leech activity, students can talk about what they did and how that is similar to what scientists do as they think about things and design testing strategies. The teacher will look over the science notebooks and discuss what worked and what was a problem with the students.


3.I.A.1 - science as a tool
3.I.B.1 - natural world questions can be investigated scientifically
3.I.B.2 - use of appropriate tools
3.I.B.3 - scientists use different kinds of investigations depending on questions they are trying to answer

References and Resources