Have a question? My team and I are happy to hear your questions and get you answers! When you type a question, it shows up not only on that experiment but also here so you can easily find your answer. You'll find question boxes at the bottom of every experiment in the program.

Question: from tntmnm about the Vector Diagrams experiment :

Why are the acceleration vectors in the video pointing upwards when the rocket is falling? Shouldn't they all be pointing downwards, since the rocket's velocity is increasing in the downwards direction? Upward acceleration arrows would mean the velocity is increasing in the upwards direction, but it is the opposite? And, wouldn't the acceleration vectors on that side of the diagram all be the same length since the acceleration of gravity is constant?

Question: from Aurora Lipper about the Homemade Pulleys experiment :

Continue with the lessons in this section, and you'll see more information on pulleys.

Question: from Aurora Lipper about the Part 5: Botany 1 experiment :

There are about 320,000 knowns species of plants.

Question: from Aurora Lipper about the Part 3: Entomology experiment :

Scientists don't know of a way to tell the age of a ladybug. It is only known that they live about a year.

Question: from sjpaulin about the Homemade Pulleys experiment :

This shows how to make a pulley, but where do you describe what a pulley is actually used for?

Question: from hannah_athauda about the Ten Static Electricity Experiments to Mystify Your Kids experiment :

Hi! Why do some materials take on a positive charge and some take on a negative charge?

Question: from arielgstorm about the Part 5: Botany 1 experiment :

How many types of plants are there? P.S. sorry for such a difficult question.

Question: from arielgstorm about the Part 4: Birds & Flight experiment :

Thank you!You are the best!

Question: from arielgstorm about the Part 3: Entomology experiment :

how do you tell how old a lady bug is? thank you! (:

Question: from Aurora Lipper about the Cosmic Ray Detector experiment :

Please try these items. 1) Instead of sanding the entire coat hanger, only sand the area where the aluminum foil will hang and the top of the coat hanger there you attach the ball of foil. By leaving the thin coating on the long part of the coat hanger, you'll help prevent electrons from leaking into the lid of the jar. 2) It is best to use really thin aluminum foil. Brand name foils can be too thick, which causes them to be too heavy for the static to push the foil leaves apart. Try getting some really thin foil from a "99 cents" type store.

Question: from chiggerbabe about the Cosmic Ray Detector experiment :

This isn't working for me. When I hold to balloon close to the foil ball, I hear a static charge from the balloon to the foil ball but the foil leaf doesn't move at all. What am I doing wrong?

Question: from Aurora Lipper about the Microwhat? experiment :

Try clicking on any of the images first. Then put your mouse directly over one of the pictures and allow the cursor to sit still for a moment. The word should then appear.

Question: from jenescobar84 about the Microwhat? experiment :

hello. I can't view the answers. What can I do to be able to know what they are ?

Question: from Aurora Lipper about the Speed and Velocity experiment :

While it is true that the worrying man's final position is only 5 feet east of his starting point, the goal of the exercise is to consider his average velocity through all three portions of his journey. Since we are calculating an average, we must consider all three velocitys.

Question: from Aurora Lipper about the Special Science Teleclass: Black Holes experiment :

An object into a black hole may reach a speed that is equal to (or higher) than the speed required to escape. But, the object is being pulled toward the black hole. That means it is just going to plow into the black hole at a faster rate.

Question: from Aurora Lipper about the Cool Blue Light Chemiluminescence Experiment experiment :

Tiny bubbles may have formed as you added the perborate, which caused it to move around. This can also be due to Brownian motion (or pedesis, from the Greek word for "leaping"). Brownian motion is the random movement of particles in a medium (or liquid), which is caused by the random movement of molecules in that medium.

Question: from Aurora Lipper about the Inclined Plane experiment :

That's okay if it is confusing at first. Don't hesitate to do the experiment again so you have extra practice!

Answer:  Convection Currents

The flakes are much larger and have more surface area, and also take on more of the water and don't move as point particles. I really like how you are experimenting! Great job!

Answer:  Three Ways to Create a Plant

Nearly all our lessons have videos, you found one of the very few that we didn't have one for!

Answer:  Instant Ice

This one is tricky because the temperature difference is so small (I recommend the Hot Icicles experiment because it uses sodium acetate which has a 70 deg F temp difference). You'll need to get the water REALLY cold so that its ready to crystallize. You can use rock salt or table salt, and if you stick the whole thing in the freezer for 20 minutes (not too much longer) that might help.

Question: from jenniferberkowski about the Special Science Teleclass: Black Holes experiment :

Student question for you: Why is it that an object falling into a black hole doesn't reach escape velocity during its decent if the gravity is so strong?

Question: from s_vedder about the Cool Blue Light Chemiluminescence Experiment experiment :

Enjoyed this experiment. We noticed that when we put the percarbonate mixture in that the particles would jump around. Why is this? Thanks!

Question: from jgeorge about the Convection Currents experiment :

We used Italian seasoning and it did not move as much as the pepper. We wonder why?

Question: from scott_pigman about the Instant Ice experiment :

Hello, I had a few problems with this experiment and I was wondering what might help. We tried it three different times—the first time, we forgot to crush the ice beforehand and the water wasn’t cold enough because not enough of the ice was touching it— but after that we couldn’t figure out what we were doing wrong. We tried leaving it in the ice for longer but it still wasn’t working… do you have any ideas?

Question: from milkbrainbaby about the Three Ways to Create a Plant experiment :

Is there a video lesson to go along with this?

Question: from dsstanford about the Inclined Plane experiment :

it was really fun but i got confused a bunch of times.

Question: from Aurora Lipper about the BumperBot experiment :

DC stands for direct current. Batteries provide direct current. With direct current the polarity remains the same. In other words, the positive connection remains positive, and the negative connection remains negative. AC stands for alternating current. Power outlets in a house provide alternating current. With alternating current the positive and negative connections switch places at a regular cycle (60 times a second in the united states)

Question: from Aurora Lipper about the Can Water Be Heated With Composting Plant Material? experiment :

Microorganisms break down plant and animal matter through exothermic chemical reactions. In other words, the chemical reactions give off heat.

Question: from Aurora Lipper about the Can a Fuel be Made From Plant Material? experiment :

Most balloons develop tiny holes when they inflate. This allows gas to escape, causing it to deflate.

Question: from Aurora Lipper about the Special Science Teleclass: Black Holes experiment :

Unfortunately, the poster is no longer available. However, I updated the link to the game.

Question: from Aurora Lipper about the Part-15 Dissecting a Chicken Egg experiment :

No, you want to use an unfertilized egg. The white cord that you see is a chalaza. The two chalazae (plural) are rope-like structures made of protein that help the yolk to remain at the center of the egg.

Question: from kristie_cooper about the Simple Hovercraft experiment :

Really fun and easy to make!!!!!!!

Question: from candjpatch about the BumperBot experiment :

What is the difference between DC and AC power?

Question: from candjpatch about the Can Water Be Heated With Composting Plant Material? experiment :

What is causing the heat in the decomposing process?

Question: from candjpatch about the Can a Fuel be Made From Plant Material? experiment :

Can you tell us why the balloon deflates a bit on the second day? Thanks.

Question: from ashley1215 about the Special Science Teleclass: Black Holes experiment :

The included links aren't working. "Download the Exploring Black Holes PDF poster file and also try playing the Black Hole Space Travel game..."

Question: from sarahdifrischia about the Part-15 Dissecting a Chicken Egg experiment :

um you said an un fertalized egg did you mean a not developed egg because the one she had was fertil you could see the white spot in the yolk but what is the embilicle cord thing called attached to the yolk.

Question: from tntmnm about the Speed and Velocity experiment :

Regarding the worrying man example. If someone saw the man right before his worry journey, left the room and then returned 4 minutes later, they would observe his displacement was 5 feet East, and conclude an average velocity of 1.25 feet per minute East. Yet that does not agree with the values you calculate?

Question: from Aurora Lipper about the Special Science Teleclass: Thermodynamics experiment :

That sentence at 12:19 is “Eyes detect electromagnetic waves.”

Question: from Aurora Lipper about the Electroplating experiment :

You may have connected the battery backwards. Be sure to connect the key to the black (negative) wire.

Question: from Aurora Lipper about the Microwhat? experiment :

The answers should still appear when using a Mac. Try clicking on any of the images first. Then put your mouse directly over one of the pictures and allow the cursor to sit still for a moment. The word should then appear.

Question: from Aurora Lipper about the Electroplating experiment :

Great! I’m glad that switching the wires solved the problem. To use salt and vinegar, use 1/4 teaspoon of salt for each 1/2 cup of vinegar.

Question: from Aurora Lipper about the Magnetic Tornadoes experiment :

The worksheet has a data table and one of the columns gives you a spot to record how long it takes for the water to drain. You can use the stop watch for that step.

Question: from Aurora Lipper about the Cool Blue Light Chemiluminescence Experiment experiment :

Yes indeed, bleach acts as a catalyst in this activity.

Answer:  Hovercraft

Feel free to substitute anything you have on hand, just keep it lightweight and easy to work with.

Question: from melindasmith913 about the Hovercraft experiment :

What if I don’t have those pieces

Question: from candjpatch about the BumperBot experiment :

Can we use one AA battery pack and one AAA battery pack instead? Both put the same amount of voltage out (3V) so would this work?

Answer:  Science Teleclass: Light & Lasers & Holograms

Please try a different device or computer. It's playing over here. What browser are you using?

Question: from irisflores25 about the Science Teleclass: Light & Lasers & Holograms experiment :

The video doesn't work. How are we able to watch them Please?

Question: from cassie_worwood about the Magnetic Tornadoes experiment :

what is the stop watch for

Question: from candjpatch about the Electroplating experiment :

Yes the key was on the negative wire. In the download materials it says you can use salt and vinegar - would this work better? What amounts/combination would be best?

Question: from teri_webber about the Keeping a Scientific Journal experiment :

Wow, coming back to the Scientific method years later, and seeing it through your eyes, has me seeing science and experimentation in a whole new light! I'm excited to infuse this excitement about trying new hypotheses and projects into my kids. They can view themselves as little scientists!! I never viewed myself like this growing up! What a gift you are offering through your program! God Bless

Question: from sanmartindayacademy about the Cool Blue Light Chemiluminescence Experiment experiment :

Is the bleach acting as a catalyst in this reaction?

Question: from briancox about the Mystifying Superconductor Roller Coaster experiment :

We can only make superconductors with very special supplies, such as liquid nitrogen.

Question: from candjpatch about the Electroplating experiment :

Hi we used copper wire and salt water and the reaction started happening and all the copper came off the wire and made the water black but no copper went on the key. What might have happened?

Question: from ko_bae about the Mystifying Superconductor Roller Coaster experiment :

AWESOME!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Question: from ko_bae about the Mystifying Superconductor Roller Coaster experiment :

Hi Mrs. Aurora, Can you make a superconductor?

Question: from mrsjorgenson224 about the Microwhat? experiment :

I hovered my mouse over the slides to see the answers, but I don't see the title. Is it because I'm on a Mac?

Question: from hs4clo about the Special Science Teleclass: Thermodynamics experiment :

What do you say around 12:19 ? Eyes detect electro... waves (sounds like electro identic waves, thinking it's an issue with the sound and it really is electro magnetic waves). Could you please confirm ?

Question: from briancox about the Predator-Prey: Who Eats Whom? experiment :

Yes indeed, fruit flies eat yeast but it is best to use a small piece of fruit as the food source.

Question: from briancox about the Science Teleclass: Light & Lasers & Holograms experiment :

Holograms look like three dimensional objects however, they have no physical substance. Cats are hunters. They enjoy playing with dot because it helps them practice hunting skills. Actually, we use the letter v to represent the frequency of the light wave, but not to represent the photon itself

Question: from briancox about the Build a REAL Scale Model of the Solar System experiment :

Here is a fraction to decimal conversion chart: https://www.hamuniverse.com/antfrac.html

Answer:  Chemical Matrix of Acids & Bases

Urea is CH₄N₂O and ammonium nitrate is NH4NO3 so they are not the same thing, nor do they act the same in a chemical reaction. You can find ammonium nitrate here. Vinegar and hydrogen peroxide mixed together is potentially toxic and corrosive ( which can break down or damage the surface you're applying it to), you'll notice people using each separately and wiping it down before exposing the surface to the other. The mixture can also cause skin, eye and tissue (like respiratory) irritation.

Answer:  Grinder Gearworks

I actually send you this in the mail after you're a member for a month, as a gift in the "hard to find parts packet" as they are difficult to find.

Question: from hannah_athauda about the Predator-Prey: Who Eats Whom? experiment :

Do fruit flies eat bread yeast?

Question: from peggy_law about the Science Teleclass: Light & Lasers & Holograms experiment :

what does holograms look like? why does cats like laser beams? why is photon v instead of a p

Question: from kajkowe about the Chemical Matrix of Acids & Bases experiment :

Hi, all sound really cool. I just have some questions before we start. Is it safe to mix vinegar with hydrogen peroxide? I always heard that's a big no-no Can I replace ammonium nitrate with urea? Ammonium nitrate is not available in my country. Thank you :)

Question: from celia_solarez about the Grinder Gearworks experiment :

Hi, where do you get the gear pullley from?

Answer:  Barrel Roof

You should have answers on the very last page of the download for each experiment. If you click on the "Live Classes" link, you'll find recordings of the detailed lectures for the concepts covered in both Grades and Topics.

Answer:  Special Science Teleclass: Physics of Motion

Sorry for the confusion, I've added the link and if you hit "refresh" you'll find it.

Question: from ukapi626 about the Slide Preparation: Heat Fixes experiment :

I think I killed the yeast when I used fire. I see nothing moving. It still looks beautiful, though.

Answer:  Alpha Particle Detector

You need to be logged into the website to view the video.

Answer:  Cool Blue Light Chemiluminescence Experiment

This item is listed in the excel/PDF download as optional if you'd like to do this experiment. It's not a requirement, and there's a special link to purchase it in the material list file for Advanced CHemistry.

Question: from ko_bae about the Alpha Particle Detector experiment :

How do I access this video?

Answer:  Detecting the Electric Field

No, unfortunately a metal 12" won't work. You need something longer, such as a yard stick or meter stick, and it needs to be made of wood.

Answer:  Newton's First Law of Motion

Yes, your son is correct! The lighter car will reach the finish line first.

Question: from celia_solarez about the Build a REAL Scale Model of the Solar System experiment :

Is there a link to the decimal/fraction conversion chart shown in the video?

Question: from amandapacker36 about the Special Science Teleclass: Physics of Motion experiment :

Where are the links for the student pages to download?

Question: from kuplinger about the Cool Blue Light Chemiluminescence Experiment experiment :

I'm disappointed to purchase yet another item. We had been told all we needed was the Chem C1000 kit in May/June. Science class is adding up very quickly....I hope there are no more surprise costs this year.

Question: from lorenavcolon about the Detecting the Electric Field experiment :

Would a metal 12’’ ruler work?

Answer:  Part 6: MORE BONUS CONTENT: Measuring Photosynthesis

Yes, give it a try! When doing this experiment, I usually suggest trying several different versions using different leaves so you can identify the best one.

Question: from sourcefiremoon about the Foggy Hands experiment :

I love your experiments! <3

Question: from tiphaine_lamb about the Newton's First Law of Motion experiment :

what is the answer to the third question? my son says lighter because it can start faster

Question: from tykes2 about the Part 6: MORE BONUS CONTENT: Measuring Photosynthesis experiment :

I don't have spinach. Will lettuce or grass work?

Question: from eburdine about the Chemical Analysis on Weight experiment :

The error Andrea mentioned is when you are calculating the number of moles of H2O (time stamp 7:48) 10.3 mol C3H8 x (4mol H2O/ 1 mol C3H8) = 41.2 mol H2O, not the 4.12 mol that is written. However your final calculation is still correct because you do not use this conversion to solve for your final answer.

Answer:  Detecting the Magnetic Field

Sure, feel free to use a piece of cork. But there is no need for tape. Just stick your magnetized needle through the cork.

Answer:  Electroplating

Yes indeed, you can use copper wire, but be sure to remove any plastic insulation before connecting it to the alligator clip. If you don't have copper sulfate, you can use saltwater (just add salt to warm water and stir until the salt dissolves. So, instead of the copper strip, you can use bare copper wire and instead of copper sulfate, you can use saltwater.

Answer:  Cosmic Ray Detector

This is the same project, but we're using it in the context of particle physics.

Question: from dalas_mueller about the Barrel Roof experiment :

Hey! I am new to this and checking out this unit for my son to start with. I'm a little frustrated because nowhere in the written materials for this unit can I find the answers to the questions. Newton's Third Law doesn't come up anywhere, it's only briefly mentioned in the "answer" section of the worksheet. Shouldn't there be a place he should go to actually find out more about these concepts? I would expect this to be in the textbook reading materials for the unit but it doesn't appear to be. Thanks!

Question: from lorenavcolon about the Detecting the Magnetic Field experiment :

Could I use a cork and tape?

Question: from candjpatch about the Electroplating experiment :

Hi there can we use copper wire instead of a strip of copper? What if we bunch up a few wires together by twisting them and then attach to the alligator clip? Will it work? Can we do the same thing instead of getting copper sulfate where you said in another response use 2 copper pennies (we don't have copper coins in Australia) can we just put a bunch of copper wire in the solution and connect to a battery?

Question: from candjpatch about the Cosmic Ray Detector experiment :

This seems to be the same lesson as the previous one called Electroscope. Is it supposed to be something different?

Answer:  4011 NAND Gate:Build a Pulsating Tone Generator

The workbook you are referring to has been discontinued along with the Electronics Learning Lab by Radio Shack (such a bummer, I know!). We've left these videos up for folks that still have own these, and also we are replacing these videos with our brand new Unit 25: Electronics with Brian (which also includes live classes).

Question: from julia_y about the 4011 NAND Gate:Build a Pulsating Tone Generator experiment :

It says in the beginning of the video "Workbook 2, pg. 48". Where do I get this book, or schematics for these circuits?

Question: from cindyspam1 about the Pendulums experiment :

cool.

Answer:  Special Science Teleclass: Chemistry

Yes, it's the first item listed in the material list. Click on the link that says "Click to download worksheet".

Question: from irishernandez77 about the Special Science Teleclass: Chemistry experiment :

Is there a work handout the kids can fill out as they view the lesson?

Question: from hlnnxn about the Invisible Writing experiment :

Good golly this section is fun

Answer:  Light Tricks

Yes totally understandable. You can find these types of intro classes under "Live Classes" and click on a previous academic year, and then scroll down to the subject you'd like the intro for. These classes walk you through the introductory content for each subject.

Answer:  Ammonia Experiments

Hi there! Sorry for the delay. Yes in general if you watch the video first, near the start I will show you what each material looks like, and then walk through how to use it in the experiment. CHemicals are usually directly linked with the least expensive place to get them in the right quantity.