Looking for constellations is a fun activity for students of any age. But what many students may not understand is that even though the stars in a single constellation may look the same distance from earth, they can be hundreds of light years apart. Having them build a 3D model helps them understand this concept (and practicing scale solidifies some math skills). Check out this video to learn how to build them using spaghetti and marshmallows:

If you'd like to download the complete lesson with templates and directions, you can find it here.

Epigenetics is a fascinating field of science. If you aren't familiar with it, the epigenome is the study of how your behaviors and environment impact gene expression. I pose the question to my students- if an identical twin gets cancer, does that mean the other twin will automatically get cancer? Students will generally say no. If that's the case, then what controls gene expression?

The cell membrane, which surrounds the cell, is covered in receptors. They act as antennae so cells can send signals and communicate with one another. Cells respond to environmental signals all the time- examples could include releasing insulin when blood sugar rises, or dividing when cells die and numbers drop. (Because of this, it could be argued that the cell membrane is the control center of the cell, not the nucleus. While the nucleus holds the genetic information that is needed to make proteins, it is the membrane that acts as the guy in charge by receiving signals on how to proceed).

So essentially you could have a gene for something, but unless the cell receives a signal to turn the gene on, (in other words- copy it and turn it into a protein), the gene will remain off. You could very easily have a cancer gene but live your life cancer free if that gene remains turned off. The decisions you make in your life, which influence cellular environmental factors, play a large role in gene expression. Here are some activities you could do with your students to teach them about epigenetics:

1. NASA Twin Study: You may have heard about Mark and Scott Kelly, who are identical twins and NASA astronauts. Both twins spent time on the International Space Station, but Scott spent a lot more time- a whole year. NASA compared Mark's DNA with Scott's DNA after he returned to Earth. This was a unique opportunity to learn the impact of space and zero gravity on our DNA and gene expression. You can learn more about the study here.

2. Case Study: University of Buffalo has a TON of case studies I encourage you to check out. (They are all free, but if you want the answer key there is a yearly subscription fee). One study is called "Identical twins, identical fates?" that explores epigenetics.

3. Learn Genetics: University of Utah's learn genetics website is an amazing resource for all things genetics. They have a section just on epigenetics. The "epigenome at a glance" is a great introductory video.

4. Partner Activity: This lesson and activity introduces students to epigenetics. Students will read about the agouti mice study (super fascinating!)  and then complete a "twin" activity with a partner.

5. Bacteria Culture Lab: If you have time to order supplies, check out this lab from Flinn Scientific. Students will see the effect of temperature on bacteria growth and phenotype (it will change color). You will need to prepare agar slides and have access to an incubator.

6. Podcast: Big Biology podcast has an episode called "genes don't do crap" that features Dr. Massimo Pigliucci, an evolutionary biologist and philosopher. The episode is 16 minutes long, and I would recommend this for honors or AP students.

7. Queen Bee: Bees are a great example of epigenetics in action. The bees in an entire hive all have the exact same DNA- the drones, worker bees, and Queen are all clones. If they are all clones, then why do they look different and have different jobs? The answer is epigenetics and "royal jelly". Check out this video you can show students that explains more detail.

8. Documentary: The NOVA documentary "Ghost in your genes" investigates how our "secondary genome" helps determine our biological fates.

9. Epigenetics Game: This game has 4 levels students can work through all dealing with epigenetics.

10. Histone Model: In this download from University of Utah, you can have students build a paper histone model.

Earth's oceans are a carbon sink, which is a place where carbon is stored long term. Oceans absorb carbon dioxide from the atmosphere. It reacts with seawater, creating carbonic acid, which in turn lowers the pH of the ocean. This phenomena is known as ocean acidification. It will only get worse as we release more carbon dioxide into the atmosphere. Oceans currently have a pH of around 8.1, but it is projected to lower to 7.7 by the year 2100.

What is the impact of ocean acidification on marine life?
Research is still being conducted on this, but there are a few things we know for sure. First, organisms that rely on carbonate to build their shells and exoskeletons will have less available. These organisms include coral, mollusks, sea urchins, starfish, and zooplankton to name a few. If they struggle to build shells, they are more likely to be eaten by predators and it can create a trophic cascade up the food chain. Other impacts could include lowering the blood pH of fish, changes in reproductive ability of marine life, and impeding with organisms ability to send chemical signals.

Ocean Acidification Lab
An easy way to show students the impact of ocean acidification on marine life is by soaking seashells in ocean water with various pH levels.
For this lab you will need (per group): 3 cups or beakers, 3 seashells, water, salt, vinegar, an electronic scale, and pH paper. Seashells can be purchased at craft stores, and I've even found them at the dollar store in the craft aisle.

Start by mixing up simulated ocean water (3.5% saltwater solution). Students will put ocean water in the first beaker, 75mL of ocean water and 25mL of vinegar in the second beaker, and 50mL ocean water and 50mL of vinegar in the third beaker. Next, have students take the mass of the seashells over the course of 3 days and calculate the percent change in mass. They will see the vinegar eat away at the seashell and a large reduction in mass. You can also have them measure the pH of the liquids over 3 days and see how it changes as carbonate is released (enter discussion on buffers!)

Following the activity you can discuss ways students can lower their carbon footprint so we can slow the rate of acidification in the future. If you are interested in a powerpoint lesson on ocean acidification and a lab write up for this activity, you can find it HERE.

Have you ever tried pocket microscopes that clip onto your phone or iPad? I have tried multiple brands and have never been satisfied with the quality.... nothing even came close to what a compound microscope could do. But along came the uHandy pocket microscope and I've been pleasantly surprised at its capabilities!

How it works:

1. Start by opening your camera app or downloading the uHandy app. It's free and has a really easy interface.
   
2. The uHandy microscope comes with 2 lenses- a low and high magnification lens. When you clip on the low magnification lens you place it on literally anything- it doesn't have to be a thin transparent specimen like you would need for a normal compound microscope. (See image 1 of it on my skin).
3. You can view prepared slides by placing the slide on the light source, placing on a metal cover that holds the slide in place, and placing the microscope lens directly over the slide. In image 2, you can see the high magnification lens focused in on a mosquito wing. You can easily zoom in and out and it will auto-focus for you.
4. Want to make your own slides? You don't have to hassle with glass slides and cover slips. The uHandy teacher kit comes with tons of small clear stickers (see image 3). There are flat stickers for thin specimens and bubble stickers for wet mounts. Simply place the specimen on the sticker, place the sticker on the circular glass piece that sits over the light source, and place the phone lens on top. In image 4 I made a wet mount of pollen grains and observed them with the low magnification lens. You could also use the black high magnification clip. Also- the circular piece that sits over the light source is magnetic so your phone attaches and doesn't slide around (awesome).
   

uHandy PROS:

• The uHandy microscope is portable. Unlike a compound microscope, you don't have to worry about plugging it in. It just clips on your phone or iPad! Students could take it outside for sampling or easily move through stations in the classroom.
• While the uHandy does allow you to use glass slides, you don't need to have them. They provide stickers that you can stick the sample to. NO MORE DEALING WITH BROKEN COVER SLIPS!
• If you have students that struggle focusing a compound microscope, you don't have to worry. There aren't any focus knobs to worry about and the image auto-focuses.
• The uHandy could easily be used during distance learning. You could have it hooked up to your phone or iPad and show students through your zoom lessons.

uHandy CONS:

• The price point of the uHandy compared to other microscopes that clip onto phones is high... however I have tried other brands and the quality doesn't compare. The uHandy provides multiple lenses, no hassle focusing, and an easy-to-use app. With other brands I struggled to use the app, had difficulty focusing the image, and couldn't zoom in nearly as much.

If you are interested in trying out the uHandy pocket microscope, it can be purchased HERE.
(This blog post does not contain affiliate links. The uHandy microscope was gifted in exchange for a review).

Know that feeling of DREAD when you wake up sick and school starts in a couple hours? Or are you so mentally drained you need a day off? (Been there!) Coming up with sub plans can be more of a hassle than just showing up and pushing through. BUT, you shouldn't have to stress over sub plans. Here are some easy ideas that will only take a few minutes to prep. Choose one (or two!) and have copies made at the beginning of the year that can be used in case of emergency.

IF YOUR STUDENTS HAVE COMPUTER ACCESS
Every school has different rules on technology. Even if you are 1:1, some schools don't allow students to be on computers with a sub. But if you do have access, here are a couple ideas:

1. VIRTUAL LAB: Have students complete a virtual lab. If you use a website like PHET, there are free lab worksheets available for download when you create an account.

2. TED TALK: If students have laptops with headphones (or the sub has computer access and can project it on the screen), have students watch a Ted Talk from YouTube. Here is a free worksheet students can fill out that can go with any Ted Talk.

3. VIRTUAL FIELD TRIP: In the age of Google Earth, the virtual field trip possibilities are endless. Students can explore national parks or even the ISS with the click of a button. Provide a link for students to explore and have them write a reflection on what they saw and experienced.

4. PODCAST: Find a fun science podcast episode students can listen to and have them write a reflection. There are so many podcasts out there it can be overwhelming... here is a list of science podcasts you can choose from.

IF YOUR STUDENTS DON'T HAVE COMPUTER ACCESS
No tech? No problem.

5. ARTICLE: Have an article students can read printed and ready to go. The topic doesn't have to match your current unit, just pick something high interest. Check out this blog post where you can find free articles.

6. TEXTBOOK CHAPTER ANALYSIS: I don't often bust out the textbooks, but having students use them when there is a sub is a great option. Have students read through a section from your current unit and fill out this worksheet. You can find it free here.

7. ONE PAGER: Have the sub grab the tub of colored pencils and have students create a one-pager for a topic you have covered this year. If your students are already familiar with one-pagers, this should need very little direction. Not familiar with them? Check out this blog post from Cult of Pedagogy.

8. COLORING PAGE: There are a bunch of free science coloring pages available online. Here are some from ASU, classroom doodles, NASA, some famous scientists, or coloring nature.

What other low-prep sub plans do you have in your teacher toolkit? Leave me a comment!

I absolutely LOVE teaching plate tectonics. What kid doesn't love learning about earthquakes and volcanoes?! I've compiled a list of activities you can choose from to make this one of your students' favorite units (and probably your favorite too).

1. Why do Earth's plates move in the first place? Use this demo to show students how convection in Earth's mantle causes plate movement.

2. We know Earth's continents have been on the move for millions of years. Here is a free lesson plan from the American Museum of Natural History where students assemble puzzle piece continents to form Pangaea.

3. A fun activity teachers use to model faults is using frosting and crackers. Have students slide the crackers across the frosting to model convergent, divergent, and transform faults.

Want to avoid food products in class? USGS has foldable paper fault templates. Check them out here.

4. Here is a fun demo you could do with students to show convection with hot cocoa "plates" (and students end up with a tasty treat).

5. Have you ever tried digital choice boards? Choice boards are fun for students because they get to choose how they want to demonstrate their learning. This choice board includes 9 options ranging from a writing prompt, crossword puzzle, listening to a podcast episode, watching a YouTube video, and more.

6. Virtual Seismometer- This site has a virtual seismometer students can play around with.

7. Google Art and Culture has a ton of virtual field trips that are amazing! In this virtual trip students can explore the inside of a Hawaiian Lava Tube. You can check it out here.

8. Speaking of volcanoes, check out this lab where students see how hot spots in Earth's crust form volcanic island chains.

9. This virtual earthquake activity teaches students how to analyze seismograms and find the epicenter of an earthquake. It's free and doesn't require flash! You can find it here.

10. I love to use tarsia puzzles to help students review vocabulary before a test or quiz. To assemble tarsia puzzles, students pair up a vocabulary word on one triangle with the matching definition on another triangle. This tarsia puzzle comes in both print (PDF) and digital (Google slide) versions.

11. Does your school have access to a 3D printer? You can print out this "Mr. Faulty" box to show students how faults form with tectonic movement. The Shape of Science sells the 3D printing file for a small fraction of what you would pay to buy a pre-made one from a science supplier.

12. Looking for a digital way to review plate tectonics? Check out this interactive diagram where students click and learn about plates and faults. Following the activity they will complete a self-grading Google form quiz.

13. Google Earth has a seafloor age layer interactive! Students can explore the age of different parts of the seafloor. You could kick off your seafloor spreading lesson by having them explore this and discover where the oldest and youngest areas are located (and figure out why!)

14. Looking for a project? Have students build earthquake-proof houses and test them out! Here are directions from Science Buddies website. If you'd rather keep it simple you could also use toothpicks and marshmallows to build the structures.

Have any other favorite plate tectonics lessons? Share them in the comments!

The law of conservation of mass states that mass in a closed system will not change before and after a chemical reaction. Mass isn't created or destroyed, it just moves places. Seems simple enough, but this law can be difficult to demonstrate. It seems nearly impossible to get PERFECT data every time. And when the measurements are off by two hundredths of a gram, students are often yelling "Ah-Ha! Lavoisier was wrong!" (Sigh.....) BUT, it can lead to good discussions on where any change in mass could have come from.

Start with reviewing the difference between physical and chemical changes. (Chemical changes include: gas, color change, precipitate, temperature change, or light). Get some play doh and roll it into a ball. Place it on the scale and ask students if they think the mass will change if you change the shape of the play doh. You could also use legos or anything else you have handy.

Once they've seen that physical changes don't cause a mass change, move on to chemical changes.
Here are some labs you can use for different grade levels to teach the law of conservation of mass.

Grades 5-6:  GLOW STICKS
In this experiment students compare the mass of a glow stick before and after it has been cracked and activated. You should get relatively good data for this lab, but as you can see in the picture the mass decreased by a hundredth of a gram. Glow sticks can be found on amazon, at the dollar store, or you can stock up on them after Halloween when they go on clearance.

Grades 7-8: ALKA SELTZER BAG
In this experiment, students compare the mass of water and alka seltzer in a Ziploc bag before and after it reacts. I'll admit this is a tough one to get great data because the bag is porous and some gas will escape during the reaction. However, it's best to use a bag instead of a sealed container because with a sealed container the lid can pop off from the pressure. I've found thicker name brand bags work better than store brand, so don't skimp to save a few bucks.
One thing you can do after the alka seltzer and water reacts is to let students open the bag, release the gas, and re-weigh (see the last picture on the right). They will see a decrease in mass and learn that gases (in this case, carbon dioxide) have mass. If you'd like to check out the lab worksheet, click here.

Grades 9+: STEEL WOOL
In part 1 of this experiment, students compare the mass of steel wool before and after pulling it apart. Since it is only a shape change and not a chemical change, it's relatively easy to get perfect data as long as they pull it apart over the scale (small fragments will fall off).
In part 2, students burn steel wool and compare the burned mass to the initial mass. (Bunsen burners will give you better data than using matches or candles). What is interesting about this experiment is that the steel wool actually GAINS mass after burning. This is because as it burns it combines with oxygen in the air to form iron oxide. The addition of the oxygen atoms causes an increase in mass. It's a great experiment to get students thinking about chemical reactions and where this additional mass could have come from. If you'd like to check out the lab worksheet, click here.

Do you have any other ways you demonstrate the law of conservation of mass with students? Leave me a comment!

Normally volcanoes form at plate boundaries, but hot spots are an exception. Hot spots are areas in the mantle that are exceptionally hot, and form plumes that break through the crust. They are great evidence of plate tectonic movement because they form island chains. Take Hawaii for example- the big island of Hawaii is directly above a hot spot and is still actively growing. The further you get away from the hot spot, the older the islands are. That means Kauai is the oldest of the chain.

For a long time I was looking for a way to demonstrate to students how hot spots work. Here is a great demo you can use that only requires a few materials: an aluminum pie pan, cornstarch, water, and a candle. Check out the video to see it in action:

If you'd like a lab write-up for students, you can find it here.
Have fun!

Bored of teaching the carbon, nitrogen, water, or rock cycles? Spice things up by having students take a ride through each of the cycles with these interactive games!

In these games, students will roll a die at stations throughout the cycles and pick up paper tokens along the way. For example- in the rock cycle game, the stations include: igneous, sedimentary, and metamorphic. In the water cycle game, stations include: clouds, plants, oceans, animals, groundwater, soil, lakes, rivers, and glaciers.

To set up the game you will need to print out station cubes and fold them (cardstock works best and will extend the life of your cubes). You will also need to print and cut station tokens and place them in cups around the room.

Assign students a random station to begin at. They will start each round by picking up a paper token and placing it in their cup. Then they will roll the die and see where it tells them to go next. I let my students go at their own pace and tell them once they have 15 tokens in their cup to head back to their seats. Then they tally up where they have been and start answering the questions on their lab paper.

Students really love these games and often ask to play again the next day. I also love that it solidifies how things move through the cycles and you can even discuss where things are stored throughout the cycle. For example- in the water cycle, water molecules can be frozen in glaciers for hundreds of thousands of years. Or in the carbon cycle, carbon can be stored in fossil fuels for millions of years. If students get stuck at a station over and over it's good to discuss why.

Want to check them out for yourself? Click on the images below!