Category Archives: Lab Experiments

M&M Lab Activity

It’s a very simple lab experiment, but a good one.  Place an M&M candy in a shallow dish of water and make your observations. I found this activity on the American Chemical Society website, Inquiry in Action. Students will see how the colored candy shell dissolves and creates a pattern in the water.

There are so many ways that this activity can be differentiated for students.  It is an excellent lab for practicing the scientific method and can be used when discussing physical properties and physical changes.

The M&M Lab is also a great introductory lab for students to use when designing their own experiments.  After completing this lab, students begin to think of additional experiments that could be tested:

  • Does the temperature of the water affect the rate that the candy shell dissolves?
  • Does a frozen candy produce the same results as a candy at room temperature?
  • Does the color of the candy have an effect on the dissolving rate or pattern?
  • What happens when other types of candy are placed in water?

Give your students the opportunity to perform the M&M Lab and see what experiments they can come up with.

 

 

 

Scientific Method Practice Using Monarch Metamorphosis

This year, my 6th grade students are using a monarch to practice the scientific method.  Two of my own children volunteered to search through some milkweeds near our house so I would have a caterpillar for my classroom.  (Note #1:  The monarch will be released outdoors following our experiment.)

I started by showing the students a live monarch caterpillar that was placed in a jar with ventilation holes in the lid.  (Note #2:  The holes are punched from the inside of the lid with the sharp edges on the top of the jar lid.  This allows for a smooth surface on the inside of the lid for the caterpillar, but the jar must be handled carefully to prevent injury.  I placed red tape with the word SHARP on the top of the lid.)  A stick and some milkweed were placed in the jar.  A couple of the students could identify the caterpillar by its characteristic stripes.  Others commented that it would become a butterfly.  Some mentioned that it would make a chrysalis.  Since my students understood that the caterpillar would go through steps to change into a butterfly, I was ready to continue.

Students got out their science notebooks and I introduced the problem we were attempting to solve:  How many days will it take for the caterpillar to emerge from its chrysalis as a butterfly?  As I mentioned in an earlier post, I always remind students that they are not allowed to share their hypotheses yet.  I then asked the students to record their hypotheses in their notebooks by completing the following sentence:  I think that the monarch will emerge from its chrysalis as a butterfly on Day # _____ because . . . 

After I checked their notebooks, each student shared his/her hypothesis with the class and explained why they made that prediction.  I love hearing my students’ ideas!!  There was a wide range of guesses (12-64 days) since students were not sure how long the caterpillar had been in the larval stage, how big it would actually get before beginning to make the chrysalis, or how many days it needed to be in the chrysalis.  Students then made Day 1 observations and recorded their findings in their notebooks.  Observations are recorded daily until the butterfly emerges from the chrysalis.

This lab experiment can be differentiated for all ages and abilities.  Watching a caterpillar become a butterfly is fascinating for students at any age and is an engaging way for students to practice using the scientific method to solve a problem.

Introducing the Scientific Method: How Many Water Drops Fit on a Penny?

To introduce the scientific method, I have my students perform an experiment that answers this question:  How many water drops fit on a penny?  Before reading on any further, make your own hypothesis.  After you have done that, continue reading!

I came across this activity years ago and have used it successfully many times.  This lab activity is quick and easy which makes it a great introductory experiment.  Students are able to make hypotheses, perform an experiment, collect data, analyze results, and begin drawing conclusions.  To perform this experiment, you will need the following materials:

  • pennies (1 for each student or group depending on class size)
  • droppers (1 for each student or group)
  • small cup of water
  • paper towels or tray to set penny on
  • notebook and pencil to record results

Before announcing the question to be answered, I always remind students that I do not want them to announce their hypotheses.  I don’t want their guesses influencing others’ ideas.

I then ask the question that we are attempting to answer and students record their hypotheses in their lab notebooks.  (Some students will ask how big the drops are, so you may need to show them the dropper and squeeze a few drops out onto a paper towel or into a cup so they can make an educated guess.)  If needed, divide students into groups and then distribute materials.

Students then place the penny on a paper towel or tray, fill the dropper with water, and count the number of drops that can fit on the penny before the water runs off.  Record results from each trial.  Repeated trials make results more reliable so allow students plenty of time to repeat the experiment.  Just make sure they start each trial with a dry penny.

Students are usually very impressed with the number of water drops that fit on a penny.  I have found that this one simple experiment often leads students to begin asking more questions.  What happens with other liquids on a penny?  Does it matter if the penny is turned to heads or tails?  How many drops would fit on a dime or quarter?  There are so many ways to extend this project if time and interest allow.  Use this as an introductory experiment or a lab during a study of water molecules.  Either way, it is an easy, engaging activity that students really enjoy.

Lab Materials Identification Activity

As students begin their study of science in junior high, I like to introduce commonly used lab materials and equipment.  To complete the Lab Materials Identification activity, I set each lab material or piece of equipment on a desk or counter.  Next to it, I place a numbered index card that is labeled with the name of that piece of lab equipment.  Students move throughout the room and copy the name of each piece of lab equipment into their lab notebook.  They also make a drawing so they can easily identify it later.  Below are some of the items I include in the Lab Materials Identification activity:

  • graduated cylinder
  • meterstick
  • beaker
  • triple beam balance
  • microscope
  • microscope slide
  • petri dish
  • stirring rod
  • hot plate
  • dropper
  • test tube
  • spring scale
  • flask

Seeing some of the materials and equipment that will be used helps to build anticipation about experiments that we will be performing throughout the year.  It also makes the students feel like “real” scientists!

Let me know if you plan to try this in your classroom.  Also, feel free to give suggestions for items you would add to the list.

Starting the Year with Lab Safety

I know most junior high students would like to begin the year with explosive lab experiments, but teaching lab safety is a top priority for me.  I have developed a list of lab safety rules that I use in my classroom.  (I posted them here.)

Each year, I discuss and review lab safety rules with students.  Students are then given a copy of my lab expectations to sign and must also get a parent signature.  I keep these signed Lab Safety Contracts in a file throughout the year.

I then provide students with scenarios in which they must identify lab safety rules that are not being followed.  Students explain how the situation should be handled and ways to prevent the problem from occurring in the lab in the first place.

Teaching lab safety is essential for a successful school year.  How do you teach lab safety procedures in your classroom?  I’d love to hear what expectations you have and ways that you teach your students how to be safe in the lab.

Introduction to the Chemistry Unit

Whenever I start a new unit in my science classes, I like to give students an opportunity to have a hands-on experience right away.  Doing this helps to grab their attention and make connections to real life.

I was struggling with how to introduce the chemistry unit a few weeks ago.  I wanted students to realize that scientists had to figure out so much without actually being able to see individual atoms or subatomic particles.

I came across an activity in an older Glencoe Science textbook that would allow the students to realize that sometimes scientists are limited in how they can gain knowledge.  However, they may be able to use clues to help them figure out those things that are not easily seen.

Prior to class, I stuck one metal object (a hexnut, screw, washer, etc.) into lumps of clay.  Students were instructed to determine what object was in each piece of clay (no hints were given).  Each group was given only a toothpick to obtain information.  They were also told to make a drawing of the object hidden in the clay.

Students were engaged, frustrated, involved, and even annoyed at times.  By poking the clay with the toothpick, they soon realized that they could gain information about what was inside each piece of clay without actually pulling it apart and seeing the inside.  It gave them just a glimpse of how scientists had to discover unconventional ways to learn about the atom and its parts.

This activity was a great way to introduce the 8th grade chemistry unit.  It could effectively be used for a wide range of grades and would also be a great problem-solving or group activity.  I will definitely be using this activity with future classes!

Lab Safety Guidelines

One of the main reasons I enjoy teaching science is because I can give students the opportunity to perform labs and hands-on activities.  Although experiments and activities can be fun, my first concern is that my classroom and lab area are safe for the students.  I have established guidelines which clearly state my expectations for maintaining a safe classroom and lab.  The following rules are included in my Lab Safety Contract:

1.  Laboratory work may only be completed when a teacher is present to supervise.

2.  Perform only those procedures assigned and follow directions completely.

3.  Handle all materials, chemicals, and equipment as instructed by the teacher.

4.  Wear safety gear, such as goggles and gloves, as instructed by the teacher.

5.  Notify the teacher immediately if accidents, spills, or injuries occur.

6.  Appropriate behavior is required in the lab.

7.  Food, drinks, and gum chewing are not allowed in the laboratory.

Lab expectations are discussed at the beginning of the school year and referred to frequently throughout the year as labs are performed.  These expectations are also posted in the lab area.  Making lab safety a priority can help junior high students establish proper laboratory behavior that will be helpful in high school classes and beyond.