Educational Evolution in the Sciences

More than 20 years ago I stepped into my first classroom. Before me sat rows and columns of students patiently waiting for me to teach them something. Today when I go to school things look pretty much the same. The science curriculum has changed little over the years and I still need to cover everything from Newton’s laws of motion to kinematics and electromagnetism. I still stand in front of class and teach, but my teaching style has evolved over the years. Nowadays I strive to motivate my students to become independent learners who can dive into problems and solve them on their own.

Demonstrations, interactive activities and lab work have always been at the heart of my teaching, but in recent years I have further refined my student centered approach. One of the ways that I have done this is through the use of computer simulations from PhET Interactive Simulations. Using these simulations and the guided-inquiry materials that I have developed, students discover for themselves the relationship between many physical parameters.  

Before I lecture on the topic of simple harmonic motion, students complete the online Period of a Pendulum Lab. Using this simulation students can learn on their own what physical characteristics affect the period of a pendulum. Students enjoy working with the simulations because they are visual, easy to use, interactive, and give reliable results that can be easily checked and repeated. In my experience, students are more likely to remain focused when using these materials than listening to one of my lectures.

Online simulations reflect the growing role of technology in education. Students and teachers communicate through computers, materials are made available through learning management systems and students have access to an infinite amount of instructional content from websites like YouTube and many others. But, as Derek Muller says in The Most Persistent Myth, technology will not revolutionise education. Education is still based on the social interaction between teachers and learners. Teachers must inspire, challenge and excite students, as well as make them accountable for learning. This is the part of teaching that inspires me to continue after more than twenty years in the classroom.

Strategies to Address Learning Gaps

As the pandemic situation improves around the world, many teachers are able to enjoy face to face instruction again. I’m thrilled to be back in my physics classroom, but that doesn’t mean things are quite back to their usual routine. The challenges of distance learning meant that some students did not manage to complete the curriculum for all of their courses last year. Helping these students to catch up on learning is a top priority for me and many other teachers.

My ninth grade students had lots of fun playing the Motion Graph Matching Game. This is a great activity to review graphs of one dimensional motion.

My school in Berlin has always focused on small group and autonomous learning so we are well-positioned to tackle pandemic-related learning gaps. At the beginning of the school year, my colleagues and I are assigned to work as coaches for a group of students throughout the year. Our regular coaching meetings present a golden opportunity to check in with kids on how they’re doing in classes and how they’re feeling about being back at school. Most students have told me that they are happy to be in school again and more motivated to learn in the school setting. 

Berlin schools are also part of Stark Trotz Corona (Strong in Spite of Corona), a program to collect information and inform parents about their childrens’ academic and social/emotional progress. The program promotes assessments and individualized attention to identify areas where students need to catch up. These assessments need not be in the form of tests and quizzes, but can also be games, lab activities, and group or partner work.

Over the summer I created a motion graph matching activity to check my students’ understanding of motion graphs. The activity contains cards for each of seven possible motion scenarios. Students first work in groups to match the seven motion descriptions with the correct graphs. Then we form teams and the players randomly select a graph and have to place it in the correct location on the board. My ninth graders recently did this activity and said they enjoyed the team competition and the chance to review the kinematics curriculum.

Being flexible and willing to deviate from my standard lesson plans has helped me to identify and close student learning gaps early in the school year. My school also holds monthly team building activities with different themes to promote a feeling of confidence and community in our students and staff. Last month’s theme was mindfulness and this month our theme is personal responsibility. Bringing students and teachers together around themes that are important for their future academic and personal development is another valuable way to make up for lost time during the long phases of distance learning.

Five Fun and Easy Physics Challenges

One of my favourite things about being a physics teacher is doing demonstrations and experiments with my students. Why start a lesson with a lecture when you can arouse your students’ curiosity by bringing scientific principles to life right before their eyes? I like to start with a provocative question like:

How can you pick up a bottle filled with rice by using just one wooden skewer?

You might get some silly answers, but you’ll also see their brains start to click.

The beginning of the school year is an especially important time to spark your students’ interest in science. You’ll find many great ideas online, but they don’t always explain how to set up the experiment or the science behind it. That’s where our next Making YOU the Scientist video comes in. These physics challenges require few materials, are easy to set up, and will bring out the inner scientist in your kids and students.

Watch the video to see the five activities that introduce concepts such as the force of friction, the center of mass, adhesion and cohesion, and Newton’s laws of motion. I hope you enjoy these demonstrations and if you have any questions about how to do them at home or school, don’t hesitate to get in touch.

The Upside of Gravity

What can you always depend on, but will always let you down? Gravity! But in fact, gravity will never let you down as a topic of interest for your physics students. That’s why Step by Step Science has created some great new teaching resources on gravity over the summer.

Gravitation and satellite motion are concepts that affect our lives in ways we rarely think about. Why does the Earth go around the Sun? What is gravity? Where is the International Space Station and how fast is it traveling through space? Here’s an overview of the new gravity lessons in our Teachers Pay Teachers store. These resources include everything you need to give your students a better understanding of the motion of the objects that surround them. These lessons are available individually or at a discount in our Gravitation bundle.

Our PhET online lab resources continue to be the most popular instructional materials we offer. As I wrote in a previous post, students enjoy these activities because they are visual, intuitive and make connections to real world situations. To go along with the summer’s gravitation theme, our latest PhET simulation resource is on Newton’s Law of Universal Gravitation. We’ll be adding quite a few more of these simulation resources in the coming months.

Our Step by Step Science YouTube channel includes a gravitation playlist that contains educational videos explaining each of the topics in these instructional materials. Each exercise sheet also includes links to the videos that describe how to solve the problems that are included. A great resource for distance learners and students who need additional help.

The summer wasn’t all work and no play. I had the chance to visit our son Avery who recently began a PhD program in aerospace engineering at Cranfield University. Our daughter Olivia came down from Glasgow for a fun weekend of checking out the aviation wonders on the campus, visiting Cambridge, and exploring the English countryside. Here’s the two siblings sitting inside a Rolls Royce RB211 high bypass turbofan, one of the most successful engines of its generation (1969-1997). Avery is working on a new generation of civilian aircraft propulsion with support from Rolls Royce and the European Union.

Fun with Fussball and Physics

The Euro 2020 tournament has been a highlight of our summer so far, especially since we’ve got a serious soccer player in the family. We live in Berlin so we were rooting for Germany until they got knocked out by England in the round of 16.

There are so many physics lessons to be learned from soccer, so why not turn some of that watching and playing time into a short lesson?

In high school physics there are many opportunities to use soccer to spark students’ interest in studying the laws of energy and motion. Projectile motion, conservation of energy, Newtons laws of motion, and the Magnus effect are just a few of the concepts that players unknowingly use while plying their craft.

In today’s post we examine how to solve two different problems when the launch angle and distance are given:

(1) What initial velocity is needed to hit the center circle from the top of the goalie’s box?

(2) What initial velocity is needed to hit the crossbar from the edge of the center circle? See diagram below. 

In both cases there are two unknowns, the time in the air t and the initial velocity vi. Therefore we will need two equations to solve these problems.

The first equation comes from deconstructing the initial velocity vector into its x and y components as shown below:

vix = cos Θ • vi

viy = sin Θ • vi

Because there is no acceleration in the x direction, we can use the standard velocity equation to come up with an equation for the time in terms of the initial velocity.

vix = x/t

t = x/vix

Substituting the equation for the x component of the initial velocity yields an equation for the time in terms of the initial velocity:

t = x/cos Θ • vi

The second equation is one of my favorite kinematic equations:

Δy = vi • t + ½ • a • t2

Substituting equation 1 into equation 2 we will have a single equation with one variable, our unknown: vi.

Still unclear about these concepts? Check out our YouTube video to see if Sam can hit the crossbar and for a complete step-by-step explanation for determining the initial velocity needed to do so.

And don’t miss the penalty shootout between the father and son to see who wins bragging rights.

Step by Step Science Posts 500th YouTube Video!

The first videos in January of 2010 were on radioactivity, fission, and fusion. The 500th video completes a series on simple machines. In between, Step by Step Science has explained physics, chemistry and math to students of all ages around the world in short videos that guide them through the concepts, equations and formulas that they need to know to succeed in school.

Here are some of our most popular playlists, with selected videos and user comments.

Optics: Ray Diagrams, Reflection, Refraction, Thin Lens Equation: Topics include reflection, refraction, index of refraction, total internal reflection and the thin lens equation. This is the video series that made me realise it’s best to explain how to solve physics problems in a step by step manner. For lenses and mirrors there are about twenty different ray diagrams that students need to be able to draw. It might sound like a lot, but really they are all drawn the same way. The first ray enters the lens or mirror parallel to the principal axis and exits through the focal point and then the second ray is just the opposite — it enters through the focal point and exits parallel to the principal axis. If you can master those two steps then you are 90% there.

this is amazing! thank you for doing this!!! it really helped me with my test!! i received an A+!!!!!!!!!!!!!!!!!!

Chemical Reactions and Stoichiometry: Covers the five types of chemical reactions and stoichiometry. The beauty of video is that students can see the wonder of chemical reactions from any place in the world. Each of these videos contains a detailed explanation of the chemical reaction and one or more demonstrations showing the type of reaction taking place. Bringing the chemical reactions to life makes a powerful impression on students.

ALL OF YOUR CHEMICAL REACTION VIDEOS HAVE BEEN SO HELPFUL!!! I am not exaggerating, you have saved my life.

RC and RL Circuit Analysis: All you need to know about resistors in combination with capacitors and inductors in DC circuits. How to calculate voltage, current, capacitance and inductance. This is a very confusing topic for many students. Therefore, it is important to start at the beginning: What is meant by time equals zero seconds? When is time equal to zero seconds? From there, build up the students’ understanding, one step at a time.

this 7 min video answered more questions than all the others combined – such a well done video !! 🙂

Linear Equations: Step by step approach to writing, graphing and solving linear equations. I made this series a few years ago when I was teaching math to eighth graders. Now they have become some of my most popular videos. I am sure it is because I clearly go through the steps students must execute to solve problems for linear equations. Students want to learn, they just need someone to show them how to do it step by step.

your explanation is awesome! I never understood this topic until I saw your simplest step by step video. Thank you.

These playlists and videos have one thing in common: they break down problems and concepts into their most basic components and build student understanding through step by step explanations. Nearly all videos are under 15 minutes and fill gaps for students who may have missed class or are missing content from their teachers or textbooks.

Thank you for your support and all the great comments over the past years. I am looking forward to making the next 500 videos! And we will see you in the next video.

Sink or Swim

Do you need a great activity for teaching your kids or students about the scientific process? The Sink or Swim experiment is a fun way to help students develop skills in measurement, calculation and estimation. They will also learn about the concept of density while determining whether an object will sink or float.

Wikimedia Commons

Density is defined as the amount of mass per unit of volume, i.e. the grams of mass per cubic centimeter of volume. Water has a density of 1.00 g/cm3. Objects that have a density greater than 1.00 g/cmwill sink, while objects that have a density less than 1.00 g/cmwill float.

The goal is to get a can to sit as low as possible in a container of water without sinking. Besides the container of water and some empty cans, all you need are a scale, some sand, and a ruler. Our Making YOU The Scientist video walks you through the steps to determine how much sand to add to the can to get the maximum possible density that will keep the can afloat. First you’ll need to determine the volume of the can and then the combined mass of the can and sand that is needed to get the selected density. Watch the video to get all the details on how to do the measurements and calculations.

You can find the instructions for this Sink or Swim experiment, along with some sample density calculation problems, in my TpT store. Turn this experiment into a challenge activity and give a prize to the person whose can floats lowest in the water.

Density measurements are used in the construction industry for calculating the distribution of weight for buildings, vessels, and other objects. The next time you’re planning a river trip, make sure you choose a raft or boat with the proper density to keep you afloat!

Salty Science

Did you know that you can make ice cream in a bag with just ice, salt and a few other ingredients? Salt is the ingredient that lets you chill the mixture to the right temperature to make a tasty frozen treat. The salt acts to lower the temperature at which a solution freezes. This is known as freezing point depression. You may not be familiar with the term, but you are probably aware that salt is used on icy roads to keep them from freezing in the winter, just like antifreeze is used in cars to prevent radiators from freezing or overheating in extreme weather.

All you need is ice, salt, sugar, and milk or cream to make ice cream in a bag. Spice it up by adding your favourite flavours. Ours was delicious!

Our newest Making YOU the Scientist activity explores the concepts of freezing point depression and phase changes. The freezing point of water is zero degrees celsius. In the first part of the activity you will lower the freezing point of water to below zero degrees celsius using ordinary table salt (sodium chloride). The salt will depress or lower the freezing point of the water. 

Freezing point depression is a colligative property of water. Colligative properties are the physical changes that result when a solute is added to a solvent. This experiment uses water as the solvent and salt as the solute. You could also use alcohol or other types of salts to lower the freezing point. Colligative properties do not depend on the type of solute that is added to the solvent, but on how many particles of the solute are added to it.

In the second part of the experiment, you will further explore the phase changes that take place when room temperature water is added to your salty ice water mixture. Phase changes occur when energy is added to or removed from a substance. When energy is removed from a substance, the particles of the substance begin to move more slowly and when the freezing point is reached they will stop moving and the substance will change from a liquid to a solid.

Watch the video to see what happened when we placed a test tube with tap water into our beaker of salty ice water. To further explore the concepts of freezing point depression and phase changes, check out my full write-up for this experiment in my TpT store.

Work, Energy and the Power of Rubberbands

What are work and energy and how are these important concepts related to each other? This is what I ask my eigth grade students at the start of our unit on conservation of energy.

Work is a hard term to define in physics. While sitting quietly and “working” at their desks, students often comment that they have too much “work” to do or that something is a lot of “work”. But unless you are just sitting there pushing your iPad back and forth across the tabletop, chances are you are doing little if no real work. That is because in order to do work in physics a force must be applied to an object to move it through a distance. It doesn’t matter how hard you push on something — if the object does not move, then no work is done.

A great way for students to explore the relationship between work and energy is to have them build cars that are powered only by rubberbands. Stretching a rubberband stores energy in it that can later be used to power the car. Besides the basic physics concepts, students must also consider the design and technology elements of their cars. To receive full credit in my class, their car should travel in a straight line for at least 10 meters.

After students build their cars it’s race time. Who can cover 10 meters in the shortest amount of time? To get things started, the rubberbands are wound around the rear axel of each car. In doing so a force is applied over a distance and potential energy is stored in the rubberband. This gives the rubberband the potential to do work. Hold it tight, place it on the floor and away it goes, gaining velocity as potential energy is converted into kinetic energy.  

Popsicle stick catapults and spinning cup helicopters are other great activities that help students learn about how energy can be stored in elastic materials and then put to work. Work and energy, you can’t have one without the other.

To learn more about this topic, check out my full energy, work and power playlist.

The Power of Electromagnets

Need to sort through all that junk in your basement? Why not build an electromagnet to do the job for you.  An electromagnet is a special type of magnet that is created when a current flows through a coil of wire. These magnets separate materials that contain iron from those that don’t.

You can build your own electromagnet by watching a demonstration in our latest Making You the Scientist video. A related lab activity from our TpT store helps students investigate the relationship between the number of times a wire is wound around a metal bolt and the strength of the electromagnet. The activity contains detailed instructions and a guide to  collecting data, constructing a graph and interpreting the data.

 The main advantage of an electromagnet over a permanent magnet is that the strength of the magnetic field can be adjusted by controlling the amount of electric current. Electromagnets are widely used as components of other electrical devices, such as motors, generators, electromechanical solenoids, relays, loudspeakers, hard disks, MRI machines, scientific instruments, and magnetic separation equipment. They are also commonly used for picking up and moving heavy iron objects such as scrap iron and steel.

Even if you don’t have a pressing need for an electromagnet in your home, the process of building and testing one is a great way to experience the scientific process, and will make You the scientist.