Use this battery and bulb experiment to teach kids about electrical circuits. For each pair of students, you’ll need a 1.5-volt light bulb, a battery, and a strip of aluminum foil. To promote inquiry, just tell them to light the bulb!
Ms. Sneed Uses a Battery and Bulb Experiment to Promote Inquiry
Our favorite fourth grade teacher, Ms. Sneed, grinned. “You’re going to love this physical science experiment!” she told her student teacher, Mr. Grow. “The first activity in our electricity unit involves batteries and bulbs. It’s super simple. We give each pair of students a light bulb, a battery, and a strip of aluminum foil. Then we ask them to find as many ways as possible to light the bulb.”
“Isn’t that too easy?” asked Mr. Grow.
“Not at all. You’ll see. Help me gather the materials. This fun little activity will scaffold kids to simple circuits, conductors and insulators, and finally, series and parallel circuits.”
Materials
Mr. Grow headed to the science cabinet. After locating the bin labeled “electricity,” he began digging out the materials.
“Wait just a minute,” laughed Ms. Sneed. “We need batteries and bulbs with similar voltage.”
“Huh?”
“We’ll use these rechargeable AA batteries. If you look closely, you’ll see that they have 1.2 volts. If we don’t have enough of those batteries, we can also use other AA, A, C, or D batteries. Although they’re different sizes, they all have 1.5 volts.”
Mr. Grow looked surprised. “I thought the bigger batteries were stronger.”
“Nope. And we need bulbs with similar voltage. For example, this bulb works in a lamp. It has 120 volts. Obviously, a 1.5-volt battery would not light it.” She pulled out a small package of 1.5-volt light bulbs. “But it will light these.”
Mr. Grow still looked a little confused. “If you try it yourself,” Ms. Sneed said, “you’ll understand the concept so much better. Why don’t you join a lab group tomorrow? Then you can do the experiment with the kids.”
Try, Try Again – Teaching Persistence Through Inquiry
The following day, Mr. Grow sat beside a fourth grade student named Marissa. “This is easy,” she said. “We just connect the light bulb to the battery with the aluminum foil.”
Marissa held one end of the foil on the positive end of the battery and the other on the metal tip of the bulb. Unfortunately, nothing happened. “What?” she cried. “Our bulb is broken. Ms. Sneed! Our bulb doesn’t work. Please give us another one.”
Mr. Grow noticed that several kids were calling to Ms. Sneed for new bulbs or batteries. She just smiled and nodded. “Hmm. I’m sure they work. Before the lab, I tested them all. Keep experimenting.”
Marissa huffed in annoyance. “Why won’t she just tell us? Can you give me a hint, Mr. Grow?”
“Sorry, Marissa, I don’t even know myself. Let’s keep trying.”
Marissa decided to hold one end of the foil on the positive end of the battery and one on the negative end. “Ouch! That burns!” she moaned.
Ms. Sneed evidently heard Marissa’s cry. “If it’s hot, let go!” she told the class.
“Hey, Marissa,” said Mr. Grow. “Heat is energy. That tells us something is happening. Let’s try setting the light bulb on top of the foil.” Still nothing happened.
Now Mr. Grow was getting frustrated with the battery and bulb experiment. But Ms. Sneed insisted that they keep trying. Inquiry learning really required persistence!
Then, as Mr. Grow held the bulb on top of the positive end, Marissa connected one end of the foil to the negative end. As she was trying to touch the other end to the tip of the bulb, the foil brushed the side of the bulb — and it lit!
Finding Additional Solutions
Around the room, Mr. Grow could hear shouts. “We did it!” students yelled. As he looked at the pairs, he could see some with lit bulbs (and faces) and others still working.
“Once you find a solution,” Ms. Sneed said, “draw it on your lab sheet. Then try to find more. I’ll tell you that there are at least four configurations that will light the bulb.”
Mr. Grow noticed that Ms. Sneed was now moving to each group to ensure that they found at least one solution. Once they experienced success, she quickly moved away to let them find more configurations on their own.
Ms. Sneed’s Class Makes Generalizations About the Battery and Bulb Experiment
“Let’s finish up!” Ms. Sneed called.
A few minutes later, she called everyone to attention. “I’d like to make a classroom display.” She held up a paper light bulb and a paper battery. “Raise your hand if you’d like to share a configuration that worked. Then I’ll call you up here to show it. After you arrange the battery and bulb, we’ll glue it to this construction paper. Finally, you’ll draw a line with with a marker to show how the aluminum foil connected them.”
Mr. Grow watched as Ms. Sneed called kids to the front of the classroom. She asked the other students to confirm whether it would work or not. Soon, six solutions* hung on the wall.
“Now we’ll make a generalization,” said Ms. Sneed. “Who can explain how to light a bulb with a battery and a piece of aluminum foil?”
After a few minutes of wordsmithing, Ms. Sneed typed their statement and hung it with their generalizations:
- One end of the foil must touch one end of the battery.
- The other end of the foil must touch one end of the battery.
- The other end of the foil must touch the side or tip of the bulb.
- The side or tip of the battery that isn’t touching the foil must touch the other end of the battery.
Mr. Grow smiled. Finally, he understood how to make a circuit. More than that, he understood Ms. Sneed’s motivation for using inquiry in her science class.
Ms. Sneed Explains the Light Bulbs and Batteries Experiment
“We’re not done yet!” exclaimed Ms. Sneed.
She picked up a marker and drew one configuration from the day’s experiment. “This is an electrical circuit. Remember when we learned about atoms? Well, in a circuit, electrons flow from atom to atom. This is called current electricity.
“The battery supplies the force for this current. It has two electrodes, the anode and cathode.” Ms. Sneed pointed to the negative and positive ends of the battery. “When the foil is attached to both, chemical reactions occur inside the battery. One reaction causes the anode to become negatively charged. The other causes the cathode to become positively charged. This forces electrons to flow through the foil from the anode to the cathode.”
Mr. Grow listened with interest. Evidently, Ms. Sneed had reviewed the process and vocabulary prior to the lesson. She was definitely not flying by the seat of her pants.
“However,” Ms. Sneed continued, “our circuit also has a resistor: this light bulb.” She pointed to the drawing and picked up her marker. “The electrons flow from the anode through the foil then to the side of the bulb.” Ms. Sneed traced the path. “If you look closely, you’ll see that the filament inside the bulb is attached to the side. It continues through the filament and out through the tip. Then it goes back into the battery.”
“The path must be closed,” Ms. Sneed said. “It’s like your circulatory system. Your heart forces your blood to move through your veins and arteries in a continual cycle.”
Mr. Grow sighed. When he watched Ms. Sneed teach, he realized that even the smallest details helped kids understand. Using an analogy drove the concept home. With practice, he hoped he could become a master teacher too.
