## Content of Elementary Science: Topic #10

Topic #10: Sound and Light

Activity #1: Sound Waves (November 27, 2017)

The purpose of this four-part activity was to introduce and observe the properties of sound waves and how sound moves through different mediums. The first part, Dancing Salt, involved holding a vibrating tuning fork near a cup covered with plastic wrap and a pile of salt on top. We observed that the vibrations of the sound waves caused the air molecules to oscillate, transferring the sound energy to the salt, which also began to oscillate (which is why it’s called “dancing” salt!). The second part of the activity, Singing Wine Glass, observed how sound waves travel along the bottom of a wine glass and bounce back to a person’s ears when he/she rubs a slightly wet finger around the rim of the glass. The Amazing Fork activity involved tying a string around a fork, wrapping the ends of the string around the index fingers, and putting the fingers into the ears. When the fork hit against the table, we observed that the sound waves travelled through the strings, through the fingers, and into the ears, producing a loud sound. The last part of this activity, Longitudinal and Transverse Waves, was completed using a long slinky. One person held each end of the slinky and took turns oscillating it back in forth in order to illustrate the longitudinal (left/right) movement for sound waves and the transverse (up/down) movement for light waves.

I would introduce the concept of sound to my students by first explaining how sound waves work and how objects can sound different through different mediums. I would have students come up with a list of various sounds they come across in their daily lives. Students could then get into small groups and complete sound activities, such as the Dancing Salt and Amazing Fork tasks.

Because students may have difficulty understanding how similar objects can produce different sounds and how sound waves work to produce sounds, the lesson on sound could be made easier by having students describe different sounds and their properties (loud/soft, high/low, etc.). Another idea for an activity that I came across in my research would be a homemade xylophone using glow sticks and glasses filled with different amounts of water (http://www.playathomemomllc.com/2011/07/glow-sticks-thinking-outside-the-box/). Hitting the glasses would produce different variations of sound and the glow sticks would add fun colors to make it appear more like a xylophone!

Activity #2: Light Box (November 29, 2017)

This activity involved the use of a light box and three mirrors (plane, convex, and concave) in order to observe how light rays reflect from each of the mirrors at different angles. The plane mirror caused the light rays to reflect at an angle less than (an acute angle) the original light ray. The convex mirror caused the reflected light rays to spread out and the concave mirror caused the reflected light rays to focus together. The purpose of this activity was to observe how light waves reflect off of three different types of mirrors.

The lesson on light could be introduced to students by first explaining how light waves work and how light can appear differently after being reflected from different objects. I would perform the light box activity with the whole class using a larger light box set-up and then having the students discuss their observations in smaller groups.

Difficulties with this activity may include differentiating between the different types of mirrors, as well as sketching the reflections of the light. As mentioned before, this activity could be made easier by using a larger set-up for the whole class in order to ensure that all students understand how to complete the activity. Another fun extension would be to use colored lights to observe the reflections!

## Content of Elementary Science: Topic #9

Topic #9: Electricity and Magnetism

Activity #1: Electrical Circuits (November 15, 2017)

The Electrical Circuits activity was performed in order to model how circuits work by using a battery (or batteries), wires, and a power source to turn on a light bulb. The purpose of this activity was to show the difference between a series and parallel circuit, as well as how the voltage of a battery affects the brightness of a light bulb. Throughout the activity, we observed that lights are brighter in a parallel circuit due to the larger voltage running through the circuit. We also determined that if one light bulb burns out in a series circuit, then all of the light bulbs will burn out. On the other hand, if one light bulb burns out in a parallel circuit, the rest of the light bulbs will stay on.

Having students build their own circuits would be beneficial in order to introduce the concept of electricity in my classroom. I would have students experiment with different factors, such as the number of batteries, the number of light bulbs, and the two different setups (series and parallel), in order to observe how electricity flows through circuits in different ways.

Difficulties with this activity may include differentiating between series and parallel circuits, as well as the voltage differences between the two. This could be made easier by explaining that series circuits only have one path, in which the voltage is “shared,” whereas, parallel circuits have two paths. As mentioned before, this activity could be changed by having students play with the number of batteries and the number of light bulbs in order to observe the flow of electricity through different paths.

Activity #2: Magnet Activity (November 20, 2017)

In Part 1 of this activity, we sorted various items based on whether they were magnetic or not magnetic. We then tested our predictions by using a magnet to observe whether it attracted the objects or not. The magnetic items were paper clips and a compass and the non-magnetic items were pennies (copper), poker chips (plastic), aluminum foil, and a wooden spool. In Part 2, we examined the poles of a magnet, observing that like poles (north-north and south-south) repelled each other, whereas, opposite poles (north-south) attracted each other. Part 3 involved observing how a cow magnet attracted iron fillings in order to determine which part of the magnet was the strongest. We observed that the ends, or poles, of the magnet were stronger than the middle and therefore, more iron fillings were attracted to the ends. The last part of this activity was to make an electromagnet using a hand generator for the electricity component and wire wrapped around a nail for the magnetism component. We observed that when the generator is cranked, the connected light bulb turns on and the nail is able to act as a magnet and pick up paper clips. The purpose of this four-part activity was to introduce magnetism and to better understand how magnets work.

The topic of magnetism, as well as electricity, could be introduced to elementary school students by having them complete an activity that allows them to predict which materials a magnet will attract and which materials a magnet will repel, or not attract. Similar activities to those we completed in class would provide a clear overview of electricity and magnetism in terms of the strength of the poles and how electricity works alongside magnetism to provide every day objects, such as disk drives, motors, generators, and speakers.

Students may have difficulty differentiating between items with magnetic properties and those without. They may also have trouble with the electromagnet attracting paper clips because the wire must be tightly coiled around the nail. Changes to this activity may include using different objects to observe their magnetic properties, as well as providing fun, interactive games, such as a fishing game for magnetic objects, a magnet maze, or an activity where students can make their own magnets (depending on the grade level).

## Content of Elementary Science: Topic #8

Topic #8: Solar System

Activity #1: Phases of the Moon (November 8, 2017)

The purpose of this activity was to exhibit the phases of the moon as they appear from Earth. In this activity, we used a styrofoam ball and a flashlight to model the rotation of the moon around the Earth and how the sun’s light affects the appearance of the moon. We observed four moon phases (new moon, first quarter moon, full moon, and third quarter moon) in terms of their appearance, time of day for rising, time of day it is overhead, time of day for setting, and time of day it is hidden.

I would introduce this activity to my students by explaining why the phases of the moon occur—the rotation of the moon around the Earth. It would also be beneficial to explain the difference between waxing, which is when the the moon is increasing in brightness and moving towards a full moon, and waning, which is when the moon is decreasing in brightness and moving towards a new moon. In order to provide a visual representation of the moon phases, the students could then get into small groups and model how the moon appears as the sun’s light travels to the moon and then to a person’s eyes by using the styrofoam ball and flashlight. Observing the appearance of the moon at different times of the day during this activity can help student’s better understand how the phases of the moon occur.

Students may have difficulty with this activity in terms of understanding the difference between waxing and waning and how the phases of the moon differ in appearance. It may also be difficult for students to understand the moon’s position in the sky during certain times of day. This could be made easier for students by having them make their own diagram of the phases of the moon so that they can more easily observe the order and the times for the rising and setting of the moon for different positions.

Activity #2: Earth’s Seasons (November 13, 2017)

During this activity, we observed the seasons the Earth experiences due to the tilt of the rotational axis of the Earth with respect to its orbit around the sun. Using a styrofoam ball to represent Earth (with a line of tape to represent the equator) and a flashlight to represent the sun, we observed the amount and intensity of sunlight as we rotated the Earth around the sun at a tilted angle in order to determine the season. We demonstrated four positions to correlate with the four seasons in the northern hemisphere: Summer Solstice in June, Fall Equinox in September, Winter Solstice in December, and Spring Equinox in March. The purpose of this activity was to model the relationship between the Earth and the sun in regards to Earth’s seasonal changes.

In order to introduce the concept of seasons to my students, I would have them perform a similar activity in small groups. Being able to have a visual representation of how the seasons change, as well as being able to complete a hands-on activity would be beneficial for students’ understanding of the four seasons. However, students may have difficulty understanding how the angle of the Earth’s tilt affects the seasons that Earth experiences as it rotates around the sun. Furthermore, students may struggle with the seasonal differences between the northern and southern hemispheres—for them, it wouldn’t make sense that the Summer Solstice occurs in December, for example. In order to extend this activity, the students could observe the seasons of both the northern and southern hemispheres to better understand the differences.

## Content of Elementary Science: Topic #6

Topic #6: Energy, Motion, and Forces

Activity #1: Hot Wheels (October 25, 2017)

The purpose of this activity was to examine the difference between kinetic and potential energy by observing the motion of a Hot Wheels car on its track. We observed the car’s motion by releasing the car at four different beginning heights (20 cm, 25 cm, 30 cm, and 35 cm) and observing the ending heights (in centimeters) for each. The ending heights were 13 cm, 16 cm, 22.5 cm, and 26 cm for each of the beginning heights, respectively. Our results indicated that the car was moving faster at the bottom of the track and therefore, had more kinetic energy, or energy in motion. On the other hand, the car had more potential energy, or stored energy, at the top of the track. We observed that the ending height of the car was smaller than the beginning height, which indicated that energy was lost due to friction of the wheels on the track.

IMG_4761 (Video of car being released from 20 cm)

I would introduce the concepts of kinetic and potential energy to my students by having them perform a similar activity, in which they are able to observe the relationship between energy and motion through kinesthetic learning. Students would be asked to release the car at different heights on the track and observe their ending heights in order to understand how kinetic and potential energy relate to the car’s motion on the track.

With this activity being hands-on, students may have difficulty staying on task in terms of completing the activity as stated, meaning that they could possibly start goofing off or throwing the cars around, depending on the age group. Another difficulty with this activity may be accurately measuring the beginning and ending heights, as some students may have trouble properly using a ruler.

A change to this activity could be using different objects—for example, smaller balls with different masses, such as marbles, ping pong balls, or rubber bouncy balls. Students could also make changes to the track in order to observe how different pathways for the car could change the relationship between kinetic and potential energy.

Activity #2: Simple Machines (November 1, 2017)

This activity served as an introduction to the six different types of simple machines: lever, pulley, wedge, inclined plane, wheel and axle, and screw. We began the activity by listing the six simple machines and brainstorming our own examples for each. Then, we looked in our toolbox and found five tools with which we were most familiar: claw hammer, screwdriver, pliers, pincers, and wrench. Of these five tools, we observed that the pliers, pincers, and claw hammer used a lever, while the screwdriver and wrench used a wheel and axle. After looking through the toolbox for different types of simple machines, we built a Lego version of a lever in order to observe the parts of the lever, including the load and the pivot, or fulcrum.

I would introduce this activity to my students by explaining each of the six simple machines and as a class, creating a list of common, everyday examples of each. The students would then be given a toolbox with different tools and asked to separate them into groups based on which simple machines they use.

Difficulties with this activity may include being unable to properly identify a tool and its simple machine, as well as confusing the differences between simple machines. This could be made easier by providing students with examples of simple machines that they encounter daily, such as window shades (pulley) and ramps (inclined plane). A change to this activity could be having students do a scavenger hunt (if possible) for simple machines, either in the classroom, around the school, or on the playground.

## Content of Elementary Science: Topic #5

Topic #5: Chemical Reactions

Activity #1: Chemical Reactions: Mixing Baking Soda and Vinegar (October 11, 2017)

In this experiment, we observed a chemical reaction by mixing baking soda and vinegar. We first poured 30 mL of vinegar into a plastic cup. We then poured one spoonful of baking soda to the vinegar and observed whether the mixture produced bubbles. The mixture continued to bubble after each spoonful was added until it stopped bubbling at eight spoonfuls. The point of this activity was to demonstrate a chemical reaction between baking soda and vinegar (bicarbonate + acetic acid = carbonic acid + acetate).

By explaining the differences between physical and chemical reactions—physical changes do not produce new substances, whereas, chemical changes do produce new substances—students would be able to predict which type of change will occur when baking soda and vinegar are mixed together. Students would then perform the experiment by adding spoonfuls of baking soda to the vinegar until the mixture stops producing bubbles.

Difficulties with this experiment may include adding too much or too little baking soda to the vinegar, as well as not fully mixing each spoonful of baking soda into the vinegar. Changes to this experiment could be observing the effects of doubling the amount of either baking soda, vinegar, or both.

Activity #2: Temperature Change for Alka-Seltzer Chemical Reaction (October 16, 2017)

This activity was performed with a cup of water, an antacid tablet, a thermometer. We began by adding 50 mL of water to a plastic cup and using the thermometer to take the initial temperature of the water (74°F and 23°C). We then performed the experiment by adding the antacid tablet to the cup of water and observing the temperature change after one minute, two minutes, and three minutes. After one minute, the temperature of the water was 73°F and 22°C. After two minutes, 72°F and 22°C. After three minutes, 71°F and 21°C. We observed that the temperature change in °F was 3°F and the temperature change in °C was 2°C after the three minutes. The water temperature decreased after adding the antacid tablet because it was an endothermic reaction, meaning that energy was absorbed by the tablet, making the cup of water colder. The purpose of this activity was to demonstrate an endothermic chemical reaction (citric acid + bicarbonate = citrate + carbonic acid).

I would introduce this activity to my students by having them get into small groups and predict whether the temperature of the water will increase or decrease after the antacid tablet is added. The students would then perform the experiment in the same way using a cup of water, a thermometer, an antacid tablet, and a stopwatch. Students would be able to observe the temperature change of the water after the three minutes in order to conclude whether the chemical reaction is endothermic (energy-absorbing) or exothermic (energy-releasing).

Students may have difficulty understanding the difference between endothermic and exothermic chemical reactions. It is also possible that the thermometer may not work properly, which could skew the results. Changes that could be made to this experiment include using different materials, such as hydrogen peroxide and yeast, in order to demonstrate an exothermic reaction.

## Content of Elementary Science: Topic #4

Topic #4: Properties of Matter – Part II

Activity #1: Playing with Air Pressure (October 4, 2017)

During this experiment, we measured the air pressure of a plastic container with a glove in the opening and a hole cut in the bottom of the container. We observed that when the glove was pushed into and pulled out of the container with the hole open, the air pressure in the container remained the same. On the other hand, when the glove was pushed into the container with the hole closed, the air pressure in the container increased and when the glove was pulled out of the container with the hole closed, the air pressure in the container decreased. The purpose of this activity was to understand the relationship between air pressure and volume, as well as how force affects air pressure.

I would introduce this activity to my students by having them predict how the volume of the container, as well as the force of the glove, will affect the air pressure within the container. Students would then perform the same experiment by pushing and pulling the glove in and out of the container with the hole open and then with the hole closed. After recording their observations, students would be able to determine whether their predictions were accurate and how force and area had an effect on air pressure.

Difficulties with this activity could involve students improperly pushing and pulling the glove in and out of the container, as well as not fully covering the hole on the bottom of the container. Students may also have difficulty accurately observing changes in air pressure during the experiment. This activity could be changed and made easier by attaching a balloon to the plastic container instead a glove because it would allow students to physically blow air into the balloon, rather than having to push and pull the glove.

Activity #2: Where Does the Water Go? (October 9, 2017)

This experiment was performed using four slices of potato, two of which were sliced about four hours earlier and two of which were sliced recently, a cup of water, and salt. In the first part of the experiment, we observed that the old potato slice was easier to bend than the newly sliced potato. We then put one of the old potato slices in the cup of water and let it sit for several minutes. Upon taking the water-soaked potato slice out of the water, we observed that the old, dry potato slice was still easier to bend than the water-soaked potato slice. In the second part of the experiment, we placed a spoonful of salt on a paper towel and on a new potato slice. After several minutes, we observed that nothing happened to the pile of salt on the paper towel; however, the new potato slice absorbed its pile of salt. The purpose of this experiment was to demonstrate the process of osmosis, the movement of water from a high concentration to a low concentration. This activity also demonstrated that it is more natural for substances to mix than to separate because it was easier for the potato to absorb the water and salt than it was to dry out by getting rid of the water.

This activity could be introduced to my students by explaining the concept of osmosis and how it works. I would have students get into small groups and predict whether the water and salt in the experiment will diffuse into or out of the potato slice. Students would then be able to complete the experiment using the two old potato slices and the two new potato slices, recording their observations and determining whether their predictions were correct.

Students may have difficulty understanding osmosis and how the movement of water affects certain substances. Some potato slices may dry out more quickly than others, which would lead students to believe that the new potato slice is easier to bend. This could affect how students understand the process of osmosis. This activity could be changed by placing potato slices in cups of both regular and salt water in order to observe the different effects the water has on the potato. Changing the activity could also involve using different materials, such as gummy worms, eggs, vinegar, and milk in order to observe the effects of osmosis on the composition of certain materials.

## Content of Elementary Science: Topic #3

Topic #3: Atoms & Molecules

Activity #1: Building Molecules and Compounds (September 27, 2017)

In this activity, we built 3-D models of different compounds (oxygen, carbon dioxide, water, and vinegar/acetic acid) using marshmallows and toothpicks. The purpose of this activity was to exhibit how compounds are formed, particularly the formation of single and double chemical bonds between two or more atoms. When molecules form single bonds, they are sharing two electrons between the two atoms in order to complete the octet rule, which states that atoms will add, remove, or share electrons in order to have eight valence electrons. When molecules form double bonds, they are sharing four electrons between the two atoms in order to form a full shell and complete the octet rule.

I would introduce this activity to my students similarly to the way that we did in class. First, I would review what an atom looks like—protons and neutrons in the nucleus, a maximum of two electrons in the first shell, a maximum of eight electrons in the second shell, and a maximum of eight electrons in the outer shell. The students would then learn how to differentiate between a single and double chemical bond and how to determine the bonds being formed between certain molecules. Next, I would have the students get into groups and I would provide each group with a bag of colorful marshmallows and toothpicks. Using the same color coordination as in class (pink for oxygen, green for carbon, and yellow for hydrogen), the students would have the opportunity to create an oxygen molecule (a double bond between two oxygen atoms), a carbon dioxide molecule (two double bonds between one carbon atom and two oxygen atoms), a water molecule (single bonds between one oxygen atom and two hydrogen atoms), and a vinegar molecule (single bonds between one carbon atom and three hydrogen atoms; a single bond two carbon atoms; single bonds between one oxygen atom and one hydrogen atom; and a double bond between a carbon atom and an oxygen atom).

Students may have difficulty understanding the difference between the formation of single and double bonds. Some students may also have trouble identifying different elements and which elements can bond together to form certain molecules/compounds.

This activity could be changed by the use of different materials, such as candy (gumdrops), styrofoam balls, and cotton balls. It could also be made easier by having a group discussion, instead of individual or small group work, and showing the formation of molecules by means of a video, images, or animation.

Activity #2: Amazing Water (September 27, 2017)

During this activity, we studied surface tension by measuring how many drops of water and rubbing alcohol we could fit on the surface of a penny. Then, we sprinkled pepper in the cup of water and the cup of rubbing alcohol to determine whether the pepper would sink or float in the substance. After making these observations, we dipped a toothpick into Dawn dish soap and “pricked” the surface of the water in order to examine what would happen to the pepper in the cup of water. The purpose of this activity was to understand the physical property of surface tension and how it can be manipulated.

In order to introduce this activity in my classroom, I would begin by explaining the definition of surface tension and how it can be different among different substances, such as water and rubbing alcohol. The students would get into groups and be provided with various substances, such as water, canola oil, at least two different types of soda (Sprite and Coca-Cola, for example), milk, and rubbing alcohol. I would have them predict how many drops of each substance could fit on a penny and perform the experiment by using a dropper to measure exactly how many drops. The students could then complete the second part of the experiment using a teaspoon of pepper for each cup of liquid to observe whether the pepper sinks or floats. After the students record their results, I would have them measure the effect of soap on the pepper in the water to help them understand how different molecular structures can affect one another. The overall experiment should lead the students to the conclusion that surface tension can differ between substances—for example, water has a high surface tension, whereas, rubbing alcohol has a low surface tension.

Students may have difficulty understanding the definition of surface tension and how it relates to the experiment. It is also a possibility that students will squeeze the dropper too hard and get the substance all over their desks. One way to change this activity would be to provide different substances in order to measure their surface tensions. Another change would be to use different coins (nickels, dimes, quarters) to measure how the size of the surface affects the surface tension.