Instructional Lesson Plan

Subject: Science: Physcial Changes of Matter

Grades: 3-5

Student Outcome: The student will be able to solve a mystery using evidence gathered during a science investigation using physcial changes.

Prerequisites: Students should have been taught what physical changes are and that magic markers undergo a physical change in water. Note: The days before the experiment, discuss what physcial changes are. Also, conduct an experiment (could be teacher modeled) with a magic marker. Write on filter paper and soak paper tip in water. Watch as the water is absorbed in the filter paper and the colors separate.

Student Grouping: Whole group instruction; Cooperative groups of 4


Opening Activities:

  1. The teacher and students will review previous days experiments concerning the physical changes of magic markers in water.
  2. The teacher will use the student outcome as an introduction to the lesson and mystery.
  3. The teacher will tell what the mystery is (see example below).

    A friend of mine received a note yesterday from somebody at her work. A mystery note!!! The note wasn't signed! Listen as I read what the note says (see materials): "Dear Sally, I think you are great. Meet me at the corner store at 4:00 tomorrow. I have a surprise for you! From, your secret friend." Now, we all know she shouldn't go because she doesn't know who it is. She agreed and decided she had to find out who wrote the note. And you know what? She wants my class, because we have been studying physical changes, to find out who wrote the secret note. She knows it was written by someone at work with a black marker, so she took any black markers she could find off all the desks and labeled each one with their names so we'd know who's it is and so she could return them tomorrow. Are you up for the challenge to solve this mystery????


  1. Pass materials to each group. Each group will get one pen to test at first, but will end up testing each pen because they will be rotated every 5 - 8 min.
  2. Teams will place a black dot at the end of the filter with the pen they have. They will then put an inch of the filter in the water (NOT the black dot end). They rest is sticking out of the cup. They may need to hold the strip until it sticks naturally.
  3. Students will observe how the water seeps up the filter and to the black dot. They then will observe how the ink changes (physical change).
  4. When the ink is separated, students will take out the filter paper, lay it on their table and place it under a piece of masking tape that is labeled with the name of the person who owns the pen (pen should already be marked)
  5. Students will repeat this procedure with each pen.
  6. When the students have tested each pen, the teacher will cut up the mystery note into strips, trying to only give the strips a little bit of ink. The teacher will pass a strip to each team.
  7. Students will test the pen on the note using the same procedures as above.
  8. Teams will then compare the pens they tested with the mystery note and determine who wrote the note.
  9. Teams will share their results.

Assessment: Students will check to see if they solved the mystery correctly.

Closing: Teacher and students will review that the ink in the pens underwent a physical change. Also, that scientists can use physical changes in matter to conduct experiments to accomplish many different things.

(Experiment adapted from the Anne Arundel County curriculum guide)





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Last updated January 29, 2000