1. Standard Indicator
3.6.5
It’s About Time
Purpose
Students will observe and describe how some changes are very slow extending
and some are very fast and that some of these changes may be hard THE
to see and/or record. ACTIVITY
Materials Read Grand Canyon
National Park by David
For each student: copy of Black Line Master (BLM) It’s About Time, Peterson with your
pencil, crayons or markers students. The Grand
For each group of students: cold/flu tablet containing sodium Canyon is a great
bicarbonate, 3 transparent plastic cups, tap water, vinegar, baking example of change
soda, penny, graduated cylinder, paper towels, clock or watch, metric taking place over many,
measuring spoons many years.
For the class: wall clock
Activity
A. Pre-Activity Discussion
1. Discuss with students that when scientists perform experiments,
connecting
they are very careful to record their data (e.g., Thomas Edison across the
recorded how long each of the different filaments lasted in a
light bulb).
curriculum
2. Explain that sometimes changes occur so quickly or so slowly that English/
they are difficult to measure and record. Often, it is difficult to Language Arts
record just how quickly or how slowly a change takes place. Encourage students to
3. Ask students to think about each of the following: use the thesaurus as
How fast can you blink your eyes? they look for words to
How long does it take your hair to grow a centimeter or an inch? describe changes that
Accept all reasonable answers. Encourage students to be occur quickly or slowly.
descriptive. Make a list of adjectives
4. Challenge students to think of examples of other changes that on the chalkboard.
occur quickly and slowly. Ask: “Can you think of something that Encourage students to
happens so quickly it would be hard to measure? Can you think create similes such as
of something that happens so slowly that it would be hard slow as a snail or quick
to measure?” as a fox.
B. Small Group Activity
1. Divide the class into small groups and distribute a copy of the
Standard 6
BLM It’s About Time to each student and a set of experiment
supplies to each group.
Standards Links
(continued) 3.1.1, 3.1.2, 3.1.3, 3.2.2
Standard 6 / Curriculum Framework / Activity 4
Indiana Science Grade 3 Standards Resource, February 2003 page 223

2. Activity (continued)
2. Review with students the procedure written on the BLM It’s
About Time. Tell students that the start time is when they place
the object in the liquid and the stop time is when the change is
finished. Discuss with students how they could measure the start
and stop times. Looking at the wall clock, review how to use
seconds, minutes, and hours to measure the length of a change.
3. Encourage students to follow the directions completely and be
descriptive in their drawing and writing on the BLM. Allow
students to begin their experiment.
4. When students have had enough time to observe cup 3, ask them
to stop experimenting and finish their BLMs. Then ask them to
share their drawings and descriptions with the rest of the class.
5. Discuss with students what happened in the cups and the speed
of the changes. Most students will probably state that nothing
occurred in the third cup with the penny and water. Ask: “Do you
think a change could be occurring that is happening so slowly
that we cannot see it?”
6. Ask students: “How can we find out?” Guide students, if
necessary, to say that the cup should be observed for several days
to see if any change takes place. (Eventually, the water will
evaporate.)
7. Have students observe the penny and water for several days.
8. After several days of observation, have the students discuss the
changes they observe with the penny and water. Ask students:
“Are the water and penny the same as they were a few days ago?
Did you see the change happen?”
Questions for Review
Basic Concepts and Processes
After students have completed the activity, ask questions such as:
Were any of the changes so quick you had a hard time
seeing them?
Were any of the changes so slow that you had a hard time
seeing them?
How did you measure the change?
How did you measure the time taken for the baking soda
and vinegar to react?
Standard 6
Standard 6 / Curriculum Framework / Activity 4
page 224 Indiana Science Grade 3 Standards Resource, February 2003

3. It’s About Time Name:
1. For each reaction, be sure to record the start and stop times.
2. Pour 100 milliliters of water into the first and third cups. Pour 100 milliliters of vinegar into the second cup.
3. Put the cold/flu tablet into the first cup. Draw a picture of the change that occurs. Is it a fast or slow change?
4. Put 5 milliliters of baking soda into the vinegar. Draw a picture of the change that occurs. Is it fast or slow?
5. Put the penny into the third cup. Draw a picture of the change that occurs. Is it a fast or slow change?
Standard 6 / Curriculum Framework / Activity 4
Start time: _______ Stop time: _______ Start time: _______ Stop time: _______ Start time: _______ Stop time: _______
Indiana Science Grade 3 Standards Resource, February 2003
Cold/flu Tablet in Water Baking Soda in Vinegar Penny in Water
Describe the change that took place in each cup.
page 225
Black Line Master 1

4. It’s About Time
Teacher Directions
Distribute a copy of the BLM It’s About Time to each student. Make sure each group has all
of the supplies necessary to perform the experiment.
Instruct students to measure the start and stop time of each reaction and describe each reaction
in the box below the corresponding cup. Remind students that the start time is when they place
the object in the liquid and the stop time is when the reaction has finished. Make sure the
students understand to only do one test at a time or they will not be able to observe everything.
Allow each group to perform the three tests. When students have observed cup 3 for a while,
have them finish their BLMs, reconvene, and share their results.
Answer Key
The cold/flu tablet and water reaction is most easily observed and recorded with a clock.
The tablet fizzes and eventually dissolves.
The baking soda and water react immediately. Accept all descriptions that allude to a very
fast change.
The water and penny reaction will occur very slowly. The change is most likely to be observed
over a period of days, when the water is evaporated and the penny has changed in appearance.
Black Line Master 1 Standard 6 / Curriculum Framework / Activity 4
page 226 Indiana Science Grade 3 Standards Resource, February 2003