Substantive Education

March 15, 2010

Red Cabbage as Litmus Paper

Red cabbage is a wonderful vegetable, and not just for coleslaw.  It can also be used as an indicator in science experiments.  Currently I’m teaching a high school Chemistry class and the module we looked at today dealt with with acids and bases.  We discussed the intricacies of hydrogen gaining or losing an ion and why that produces a base, along with …well, that doesn’t matter here.

Back to the wonders of the cabbage.Most experiments involving acids and bases require you to purchase litmus paper.  Litmus paper is an ‘indicator’ and changes color when it is exposed to an acid or base.  Anyone with a pool is probably familiar with the concept.  I didn’t have any litmus paper, and seeing as how we live in the country and a trip to a school supply store is a bit of a drive, I frequently use my good friend, the red cabbage.  Here is how to use your cabbage as an indicator in your science experiment.

Chop up a section and put it into a saucepan on the stove.  Allow the cabbage to come to a boil for 5 to 10 minutes.  You now have an indicator.  Using a ladle, scoop some of the liquid (avoiding the actual cabbage) into clear glasses or jars.  You only need a little.  You are ready to test away.

This is the color of the plain cabbage juice, our indicator

We added lemon juice to the glass on the left, the glass to right has nothing added.

The glass on the left after lemon juice was added.

Collect a variety of household items and chemicals and add a few drop to your glass.  If the indicator turns red  you have added an acid, if your indicator turns green you have a base.  We tested lemon juice, ammonia, lime away, windex, coke, and saliva.  Obviously no change in color indicates a neutral substance.   Once kids get the concept they start wanting to test everything…hence the saliva…which turned out to be neuteral.

The center glass has just had amonia added.

The center glass has just had ammonia added.

Coincidently, I just covered similar material, at an easier level,  with my elementary school science class and they loved the mixing and dramatic color changes…enough that several students went home and asked their moms to buy some cabbage so they could continue to explore.  What more could a teacher ask for?

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September 15, 2009

Seperating Molecules

IMG_1234Today my Physical Science students and I were discussing atoms and molecules.  The point of the lessons was not simply that a molecule is a combination of different atoms, but really understanding that these combinations then make up unique substances with characteristics of their own.  We started with water, a great starting point because kids are familiar with it, and are most often familiar with the chemical equation for water..H2O. They can observe that water is different than oxygen or hydrogen and has it’s IMG_1237own unique characteristics.

We explored these concepts with a simple experiment.  (This experiment does use electricity, so use commonsense safety precautions.) We took two copper wires with their ends exposed and attached one end of each wire to the top of a 9 Volt battery, using electrical tape to secure it.  Do not let the wires touch each other, and do not use a stronger battery.  We then put the other  end of each wire into a glass with a solution of water and baking soda.  As soon as the wires were immersed we were able to observe the breaking down of water molecules into their atoms of hydrogen and oxygen.  As the students watched, the gases bubbled away from the ends of the wire and  we were able to discuss the concepts involved.  So, in this first phase we observed a molecule breaking down into atoms.

IMG_1238After a few minutes of observation the students began to observe another change.  The end of one of the wires was turning a bluish green.  Baking soda contains carbon atoms and when you combine hydrogen, oxygen, carbon, and copper (from the wires) you get hydroxycarbonate.  Hydroxycarbonate is that bluish green substance that we find on the Statue of Liberty which is made of copper.  In this phase of the experiment  we can watch as new molecules are formed.

Most science concepts can be taught with common household items…this one came from our textbook, love Dr. Wile, but there are experiments for just about everything online.

June 9, 2009

Teaching Physical Science? A new resource.

Thought I would pass on this book review for those of you with high school kids.  We have been doing the Apologia science books and they are FABULOUS!  They are rigorous without being difficult – clear explanations of difficult topics, an engaging writing style and clear illustrations put those Science books above most I’ve seen.

However, several of our students are 1) not ready to go on to Chemistry next year…or 2) Have finished the science that is offered by Apologia and don’t want to take an AP class.  If you have students in Grace Prep who just finished General Science I would still recommend going on to the Physical Science book as it is a good foundation for concepts that will follow in High School courses.  However this series does cover some of the same material from a different perspective and would make a great book to read along side the other, maybe as a family read aloud.

For those students who are not sure what to do next year for science, this looks like a fun, engaging, science course.  Maybe a few students would want to gather every few weeks as a ‘reading group’  for discussion..

If you have read the US history series then you are familiar with Joy Hakim.  She has begun, what will eventually be a 6 book series on the history of science.  The books fall somewhere between a Science textbook, History narrative, and just plain fun.  It is written for grades 9 and up, so I would follow your own discretion with younger kids.  I’ve included a review below by the National Science Teachers Association….who probably know what they are talking about.

The book is around $18 on Amazon, and there is a companion book with students review, exercises etc.

This is the third book in the series and the one that has received the best reviews.  There is also The Story of Science: Aristotle, and The Story of Science: Newton.

Let me know what you think
.  I think I will be ordering this one so I will put up a review when I get it on the website.

In The Story of Science: Einstien Adds a New Dimension, Joy Hakim weaves together the science, history, and personalities behind the major advances in physics over the past 100 years. The result is a fascinating tale that’s much more accessible (and fun) than the typical science text. And, it’s written with middle and high school students in mind. This is Hakim’s third book in her Story of Science series. The first two, Aristotle Leads the Way and Newton at the Center, are equally well researched and written.-American Educator, Winter 2007-2008 — American Educator

Textbook? Novel? Joy Hakim’s books are always a little of both, and this one is even more fascinating than the previous two editions of The Story of Science. This volume begins with Einstein toiling in the patent office, about to produce the amazing insights of his “miracle year.” Then, interwoven throughout the story, are the contributions of the other physicists and chemists upon whose shoulders Einstein stood. Like all of Hakim’s books, this one is filled with anecdotes, historical context, and deeper insights into the real methods of science than any other textbook has ever offered to students at this level. And most importantly, it is a joy to read! In a strict sense, this book should be seen as a foundational text for an integrated program of physical science—ideally at grade 9 or 10. There will be no mathematical barrier at this level, but there are many opportunities to link math, language arts, social studies, and the arts to the book. It would be the ideal choice as a book for a teamed middle school. But don’t relegate it to the textbook selection process. Wrap it up for your vacation reading. I guarantee you’ll learn more about physical science, about Einstein and his peers, and about the grand endeavor we call science, than you ever imagined—in the most pleasant way possible. -Juliana Texley, NSTA Web Field Editor — National Science Teachers Association (NSTA) Recommends

April 22, 2009

Using the Scientific Method to do Science Fair Projects

scientificmethod

Scientific Method

I talked about the Scientific Method in my post on Gardening Part 2…and realized that it is a topic that seems to generate a lot of confusion. I thought I would break it down for you here using a simple elementary school experiment. For those of you with children who have to do science fair projects I’ve chosen to use one of my sons to illustrate a couple of points. First, don’t be to quick to correct your children’s hypothesis’s when you see them heading in the wrong direction. Scientist learn as much from failed experiments as they do from ones that work. Second, do help your children identify variables that might change (explanation later) that is an area that most kids can’t see right away and need practice to understand.

One of my sons did a Science Fair project on how fast different liquids would freeze. (I could not find any pictures of this experiment … but I have included some other photos of past projects to give you an idea of how their finished boards looked. Gluing and designing the display is half the fun.) He was in early elementary school. Now that he had picked a topic…often the hardest part, he needed to start doing some research. Depending on your child’s age, and how much time you are investing, it is a good idea to have your child find several different kinds of sources. For instance, they can look up information in a book, search the internet, and maybe interview an ‘expert.’ (like a physical science teacher). While we did our research one of the things that he discovered was that salt (sodium) makes things freeze slowly.

caleb-17

Caleb and a science fair project on filtering water.

The next step is to come up with an Hypothesis…this is an educated guess. You guess, from the research you have done, what will happen. Well, my son was quite young, and although his research had said that sodium would make things freeze more slowly he still hypothesized that the milk would freeze quicker because it started out thicker, or more solid. When he wrote out his hypothesis for me that is exactly what he said. ‘While milk has sodium which slows down freezing I believe that the milk will freeze faster because it is already partially solid.’

Now we needed to design an experiment. This is a tricky step with many things (variables) to consider. My son chose several different liquids; tea, water, apple juice, and milk. We decided we would put some of each into ice cube trays and then check on them every 15 minutes and record what we found out.

While that gave him a general idea of his experiment, there were still a few things he needed to account for. He needed to be sure that he had controlled as many variables as possible. For instance, he decided that all of the liquids needed to start out at the same temperature, so we let the trays sit out on the counter until all of the liquids were at room temperature. He used a thermometer to determine they were all the same. He also carefully measured the amount of liquid put in each part of the trays…different amounts of liquid would yield different results. As with all good experiments he filled up several trays so that he had performed the experiment repeatedly thereby showing that his results would be consistent. Hopefully that clears up what I mean by accounting

Joseph and a project on the variety of animals in tidepools.

Joseph and a project on the variety of animals in tidepools.

for variables.

Your child needs to carefully write out the directions for their experiment (including all of the directions to account for variables.) Help them understand that the directions should be so clear that someone else doing the experiment would know exactly what to do.

Now it is time to collect data. Your data should be in a written record and if possible recorded in a concrete measurement. In our case, he wrote down a description – frozen crystals are beginning to form- and estimated what percentage of the liquid had become frozen. We did this every 15 minutes until all of the liquids were frozen. Help your child to understand that at this stage they are just recording the data, not interpreting it.

Levi with a project on dental gum removing plaque.

Levi with a project on dental gum removing plaque.

Next, we want to analyze the data. If your child is old enough to do math this is a great time to work at getting averages of your results. For instance, if we performed our experiment 4 times and the apple juice took 35 minutes to freeze in one try, 34 in another, 37 in another etc. we would add up all of those results and divide to get the average of our experiment. This gives a practical application to all that math they are learning. Most science fairs require the data that you analyze to be displayed on graphs. Luckily there are many online programs that can help you with graphs, although I found that especially for younger children, the exercise of making the graph is very instructional.

Once we have analyzed the data we are ready to interpret. Basically, was your hypothesis correct. As you might have guessed our hypothesis was wrong. The milk was by far the slowest liquid to freeze, so in his interpretation he said, ‘Although I thought that the milk being thicker would make a difference it didn’t, the sodium in the milk kept it from freezing.” As it turns out he won with this project at the fair we were at…the object is to follow the scientific method and learn from

Caleb and his wetlands experiment.

Caleb and his wetlands experiment.

it…not to get a ‘right answer’.

We aren’t quite done yet, the next step is to examine your experiment and decide if you could pursue it further what would you do – maybe find several liquids with sodium in them and test whether the amount of sodium made a difference.

Just about anything your kids are curious about can make a good science project. We’ve done experiments with friction using race cars going down slopes of various materials, where banana’s brown quicker, what surfaces snails like to crawl on, what foods rats prefer, whether the SPF in suntan lotion makes a difference, and whether fertilizer affects our wetlands. I’ve seen projects on belly button lint (no kidding) and the accuracy of shotguns. This is a great way to let your children’s natural curiosity lead their studies.

Where we compete the kids have to show their workbook (not a finished cleaned up copy – that is there too- but a messy first draft) to show that they did the work, not mom and dad. In their books they acknowledge what help they received, like typing, math they didn’t understand etc. The idea is to have your child do all of the work possible, but where they need help to offer assistance. Be careful not to ‘overhelp’. Let the project be theirs.

By the way, a fun start to a project is using red cabbage as an indicator of ph balance.  If you want more information about how to do that check it out here. There is also information about how to break water molecules down into hydrogen and oxygen here.  This information can be taken even farther if you catch the bubbles escaping in test tubes…you will see there is twice as much hydrogen as oxygen…


March 18, 2009

Learning in the garden Part 2

Filed under: Education,Science — kbagdanov @ 7:24 pm
Tags: , , ,

Okay so yesterday, in part one, we talked about the little kids, here are some ideas for the older students and a special history tie-in I’m excited to try out.

When kids reach 4th grade or so they are still really interested in doing science experiments and are ready to do themscientificmethod in a more organized fashion…using the scientific method. That doesn’t mean anything truly difficult, just that you are going to take what might have been a little haphazard (okay, you might not be haphazard, but I am) and give your experiments a bit more form. The scientific method is easy to teach and apply when you have a garden going and your children should be familiar with the steps.

First, you need a question. Does Miracle Gro actually help? Do sunflowers actually follow the sun? Does corn need cross-pollination to produce kernels?

Once you have a question you do some research and come up with a hypothesis or guess. Then you do an experiment to see if your guess (hypothesis) was correct. Analyze the results and come up with a conclusion. Following these simple steps gives your student practice in the methods real scientist actually use.

The garden provides a great science lab and kids can do several experiments, keep log books, and conduct research over the course of the growing season. Depending on your questions you can make experiments appropriate for any grade level.

3sisters-optA fun history/science tie in is to plant a Three Sisters Garden. I’d suggest checking out several websites and reading the instructions and stories if you decide to try this. A Three Sisters Garden is a method that the Native American Indians used and taught to settlers. The Indians planted the three sisters: corn, beans, and squash, together. The combination of plants helps each of them to produce fully. Corn uses a lot of nitrogen and beans produce nitrogen. Squash plants spread and provide a natural weed cover. The three also are a nutritional powerhouse when combined.

3sistersIf you choose to plant a Three Sisters Garden you can tie in history with a Native American study…you can tie in literature by reading some of the legends…or science, by experimenting with the combinations. One of the experiments that would be fun would be planting with and without fish. Traditionally, the Indians placed parts of a fish in the mound that the corn was planted on to provide the fertilizer that the heavy feeding corn needed. You can plant some corn with and some without the fish to see how it works. WARNING: I’d suggest you plant with a purchased fish emulsion as actually planting with fish will encourage wildlife, attracted by the smell, to come dig up your garden.

If your student isn’t intrigued by experimenting with botany and wants a little more excitement you might want to encourage them to make a study of beneficial and harmful insects that visit your garden. They could experiment with some of the organic methods used to control these visitors. Is it true marigolds discourage certain insects from invading….or pouring hot chili oil around the border of your plot? A little time on the internet exploring with yield up lots of ideas for research.

March 17, 2009

Learning in the Garden Part 1

sunflowersSo many fun things you can learn in the garden. I’m in the digging stage of putting in a vegetable garden and it made me remember some of our past gardening experiences, when the boys were young. No matter what the age of your kids, or the subject you’re teaching, keeping a garden can be a great tool for your school. Here are a few of the things we have done in our garden, along with a few I’m trying this year. Most of the following can be used whether you just have a patio with pots, or an acre of land. I’m starting with some activities for the preschool, early kindergarten stage…but that is not to say that your older kids wouldn’t have fun with these.

If your children are in preschool and early elementary school everything in the garden is a fascinating lesson. Watching the miracle of seeds developing into plants, flowers, and vegetables never gets old. A favorite activity for thebean young is to take a few bean seeds, soak them for an hour or two to get them started, then take a clear glass and fill it with damp paper towels. Place a few seeds around the edges of the glass so that they can be viewed from the outside but are still in contact with the damp paper towels. Don’t allow the paper towels to dry out. I had my boys draw pictures each day (or twice a day if there is a lot happening) of the changes in the seed. They may want to carefully measure the seed to see if it swells before the root breaks forth. As they watch they will see the root emerge, the original stem, and the first leaves unfurl. . Although the glass allows us to view what would normally be going on under the soil, there is a lot going on inside of the seed as well. I’d suggest getting a few books on seeds from the library before you start.

Another fun activity for the younger set is to get a fast growing seed like radishes, have the kids write their names in the dirt with their fingers, then sprinkle in the seeds. In a few weeks time they will have their name in the garden. Take a picture and enjoy a salad.

One year (so sad I can’t find the pictures) we planted a square of tall sunflowers with one opening, then, once the plants were about 4 inches tall, we planted morning glories around their base. As the sunflowers grew the morning glories climbed the stalks. With some careful twining and few well placed strings we were able to train the morning glories to make a roof and we had a gorgeous flower clubhouse. When the clubhouse ‘bloomed’ it was truly extraordinary. Adding to the fun were the butterflies and birds that came to hang out in our clubhouse.

It seems young children can’t get enough of little hiding places, so if the sunflower house seems a bit extravagantbean_teepee_5 another option is a bean tepee. All you need to do is make a tepee out of some long sticks or PVC pipe you might have around the house. (Pieces long enough to make a tepee a child could climb into.) Then run and tie string around most of the pieces leaving an opening. Plant 2-3 bean seeds (makes sure they are a climbing variety and not a bush.) at the base of each stick. As the plants begin to climb and send out tendrils help your children to observe closely. The tendrils will always wind the same direction and many of the tendrils in between plants will make themselves into curlicues. This is to protect the plant during growth and in the wind because the tendrils now have some give and won’t become taut and snap. As the beans mature they will hang down into the tepee and children can harvest them while they play. My boys liked to take a book into their tepee and ‘read’.garden-journal

Science and botany aren’t all that can be going on in your garden. How about keeping a gardening journal with careful observations, poems, and illustrations. This can be a spring writing project, the possibilities of what to include are endless. With a little intentional thought on the part of mom this could be your Language Arts time and what child would object to a lesson outside sitting in the garden drawing and writing about the plants they’ve grown. They can keep track of the insects and wildlife that visit their garden. They can group those animals into beneficial and harmful categories. A journal can be both practical observations and a time to be creative with stories, poems, songs, and illustrations that the garden inspires.

Reading time is easy to incorporate into the garden. You may choose to check out books on plants and gardening, orthe-secret-garden-harperclassics-006440188x-l maybe instead read some great literature. How about a cozy chair in the garden where you can read about Pooh’s adventures in the Hundred Acre Woods. Most little girls would love to sit in their sunflower house and read or be read to ‘The Secret Garden’. For the reluctant reader just moving your reading instruction outdoors can be inspiring.

Even math is more exciting when we are in a new place. I’m sure you can come up with garden ideas for addition and subtraction. Older children may want to figure the percentage of seeds that sprouted. Most seeds need to be thinned to a certain number of inches apart (don’t worry directions are on the seed packet) so it’s a great time to get familiar with using a ruler.

In ‘Learning in the Garden Part 2″ we’ll look at ideas for older students and how to incorporate history into your garden.

So get outside, get your hands dirty and play in the mud. Oh mud, maybe you could make some relief maps….. I’ll stop now.

October 25, 2008

Animal Grossology Field Trip

Last Tuesday we went to the Reuben H. Fleet Museum to visit the Animal Grossology exhibit, along with the rest of the exhibits. The exhibit focuses on all things gross. There are displays on a cows many stomachs, the way a fly vomits onto it’s food before it eats, and the many colors of blood. We played games about animals that use slime and games about beetles that lay eggs in dung. There were poop exhibits next to exhibits on hair balls and tape worms. It was an elementary school boys dream. Absolutely disgusting. Here are some photos…you’ve been warned:)

October 3, 2008

Masters of the Night: The True Story of Bats

Filed under: Field Trips,Science — kbagdanov @ 12:55 am
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Unfortunately, we don’t have time to go to the exhibit as a group, but for those of you who want to check it out, it looks like fun. The Discovery Center is in Santa Ana at 2500 North Main Street. For other information about the Discovery Center visit their homepage at http://www.discoverycube.org Here is the information from their website.

October 4, 2008 – January 4, 2009

Discovery Science Center is bringing the mystery surrounding bats out of the dark!

Bats are a mystery to most people. Very few have ever seen a bat up close. What little most people know comes from folklore, myth or superstition. The truth about bats is they are gentle, beneficial, and amazing animals. Their value has been overshadowed by their tainted reputation – a reputation based on ignorance and fear of the unknown. With lifelike cave piece sets, models and interactives, the ecological importance of bats is revealed, and visitors are given a true appreciation of the wonders of the bat world.

From medieval gothic lore to the beneficial nature of these agile creatures of the night, Masters of the Night: The True Story of Bats dispels misconceptions, while engaging children and adults alike. The exhibit brings the mystery surrounding these nocturnal creatures out of the dark. It’s the real story behind these fascinating animals and their unique appearance and skills.

April 7, 2008

Elementary Science

Filed under: Science — kbagdanov @ 5:42 pm
Tags: , , , ,


On Friday’s I teach some classes for students in our school. One of my favorites is elementary science. This year we are working through a great book published by Apologia called Exploring Creation with Zoolology 2: Swimming Creatures of the Fifth Day. (I highly recommend this entire series…fabulous.) This Friday we were doing a series of experiments to use for our Open House at the end of the month.

Here the girls are getting our sand ready….

Our experiment involved testing where the best fossils would be formed. We used sand, dirt (mud…the boys were a little over-enthusiastic with the water) and clay. Then we took a shell with a lot of ridges and made depressions in each of our materials. Plaster of Paris was quickly (we weren’t quick enough and had to make a second batch) pored into the depressions…and in a mere 30 minutes we could pull out our ‘fossils’ and see if our hypothesis was correct .

Here Garret (really cute guy that you can’t see) is pushing our shell into the mud.

Here Linda is working quickly to get the Plaster of Paris in place.

April 6, 2008

Chemistry

Filed under: Science — kbagdanov @ 5:19 pm
Tags: , , ,


One thing I’ve learned about doing science with High School students is that most concepts that they are learning can be demonstrated with common household chemicals. It’s amazing the number of concepts that can be taught with vinegar, baking soda, a balloon, and liter bottle.

On Friday my Chemistry students were doing a more advanced experiment using conversions and stoichiometry to figure the pressure of the gas within the balloon.

Once we figured the Radius of the balloon, then the volume of the balloon, found the atmospheric pressure, temperature, water vapor pressure we could calculate the pressure of the CO2 that was formed. Okay, all of that took a while and we are all very grateful for calculators. Then we could figure the moles of CO2 used in the reacation…to (with the magic of stoichiometry) figure that 4.50% of the venegar was acid. YEAH!!!

Quality Chemistry instruction all with items from the kitchen….all kitchens have extra balloons, right?

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