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Wednesday, December 26, 2012

Weather Observations

Its one thing to tell students that rainy weather is associated with low air pressure and sunny weather with high pressure. Students will get a better grasp with a weather log which can be tailored to the age level.

An example is a kindergarten through third grade weather log.
1. Make a bulletin board or large chart in which students can put the classroom observations for everyone to see.
2. Teach students to identify the three basic cloud groups, stratus, cumulus and cirrus.
3. Daily, allow students to observe clouds as they spend time on the playground, pass a large window going to lunch or restroom or on a deliberate trip outdoors to look at the clouds.
4. Record on the chart the date, weather (rainy, fair, snow), clouds present.

Before beginning activity, I would have students to make a cumulus, stratus, cirrus, sunny day, rainy day, snowy day picture. Each day when the class records the weather, allow one student to lead the line to lunch, restroom, playground and of course use their picture on the bulletin board for that day.

Students should recognize patterns such as rain and stratus clouds. They may notice cirrus clouds are followed the next day with rain. You can discuss that there are many names for clouds. Mackerel sky comes to mind. Every region has their special names. My mother always points out a "Buttermilk Sky" by Hoagy Carmichael. This is the link to a youtube presentation of Buttermilk Sky by Hoagy Carmichael.
Teach weather lore that describe cause and effect patterns of weather such as "Red sky at night sailors delight, Red sky in morning sailors take warning".

For grades 4 and above, an individual weather log is more appropriate. The cloud and weather activity is appropriate through grade 6. At grade 6, you should add air pressure. However, I would like to see any of you get eighth graders excited about leading the queue to lunch.

In grades 6 and above, there are deeper patterns that students can observe such as the correlation of air pressure with a weather system. I had students record data on a weather log they kept for six weeks. Unless you live in a climate where it rarely rains, you should be able to show the correlation. In arid climates, you can keep the log and teach the concept of air pressure and when rain or vertigo occurs, revisit the topic.
Date
Temperature
Weather
Cloud cover
Air Pressure
Dewpoint













































I used a computer monitor and weather.com to get the daily data. If you spend too much time doing the log each day, you really don't get much accomplished. If you can't display data from an active source, record the daily data on your whiteboard, etc. for students. Ideally, your school has a weather station that records the outdoor air pressure, temperature.

Thursday, December 20, 2012

Dewpoint and Relative Humidity Labs

Both of these labs can be done in one day.  For dewpoint, I used glass beakers. I have known teachers to finally have a use for all those glass babyfood jars they saved. One teacher carefully saved cans from canned vegetables she used at home. The metal is very quick to show condensation.


Dewpoint lab

Air temperature _________

Temperature of water _________

Slowly add ice to water.

Temperature of water when you first see dew __________

Temperature of water two minutes after you first see dew ______

Why is dewpoint more accurate when you first see dew?
___Dew is produced at dewpoint and lower temperatures.________

Where does the dew come from?
___The air surrounding the container.____


Humidity lab

Dry bulb reading _________ 
Air temperature.

Wet bulb reading _________
Wet gauze is tied to the base of the thermometer. You can use a sling psychrometer which has two thermometers. One of which has a wet gauze attached.


Difference between the dry bulb and wet bulb reading ______

The greater the difference between the dry bulb reading and the wet bulb reading, the drier the air is. More evaporation occurs because the air is able to hold more moisture. When the air is totally saturated, no more water will evaporate and the dry and wet bulb readings will be the same.

These charts produced by University of Waterloo in Ontario, Canada were the best charts. I liked having students use charts. You will also find calculators and formulas that take into consideration air pressure. These charts give good results. The biggest mistake I see is people using a heat index chart which is a different concept.

http://retirees.uwaterloo.ca/~jerry/orchids/wet&dry.html



Relative humidity __________

The ___________ (greater, less) the temperature difference between the dry bulb reading and the wet bulb reading, the drier the air or lower the relative humidity will be.

Tuesday, December 18, 2012

Fun with Pepper

I've got two entirely different concepts that are illustrate by these two activities.

Activity One: Magic Pepper

Give students a mixture of salt and pepper. Perhaps a 1/4 to 1/2 teaspoon on a paper towel or desktop.

Give students a plastic spoon and a piece of wool. Have them rub the spoon on the wool to create a charge.

Allow students to hold the charged spoon over the salt and pepper.


  • Note the pepper rises more easily due to it being lighter.
  • Both salt and pepper will be attracted to the charged spoon. Salt is ionic. The pepper has polar covalent qualities.


You can whisk the leftover salt and pepper on the floor and the custodian shouldn't notice or be tidy and carry the rubbish bin around the classroom and whisk what is not used in.

Activity Two

Mix pepper in water. You will notice that the pepper floats. This is because pepper is not soluble in water. Take a toothpick, dip it in dishwashing detergent. Touch the soap laden toothpick on the surface. Observe what happens.

The explanation I have heard is this occurs because the dishwashing liquid reduces the cohesion between water molecules and this causes the pepper to move.

I suspect that the dishwashing liquid creates an emulsion and disperses the pepper. Sound in your thoughts please.

Monday, December 17, 2012

http://sciencewordsearches.blogspot.com/

I've begun a word search blog. For followers in the UK, Canada, Australia, if you will send me the spelling you use; I will remake the word search for you and others in your respective countries.

I will first post wordsearches that I find on my computer files. I am very sorry there are not keys. I personally do not like wordsearches. Many students do. Since it is a good way to practice and become familiar with vocabulary terms, I made them. Children who finished before others would often hop to the pleasure of doing a wordsearch. Any future wordsearches will have a key.

Static Electricity

This is an incredibly simple and fun activity.

Materials:
Roll of clingfilm or plastic wrap. In the United States, Reynolds brand tends to work the best.
Roll of paper towels
Small bits of paper (Empty the hole punch ;=] )
Equally small pieces of aluminum foil, rubber bands, salt, pencil shavings, plastic.

Part 1
Distribute a square or rectangle of plastic wrap and paper towel to each student.
Have students flatten the plastic wrap on their desktop.
Next, students rub the plastic wrap with the paper towel.
As they rub, ask them what they think the plastic wrap will do if they lift it by opposite corners. Invariably, they will say it will wad into a ball or similar answers.
After a minute or two, have students place the paper towel aside.

Instruct students to lift by opposite corners. Surprisingly, the wrap will open instead of collapsing. This is because they created a charge on the opposite side, thus creating the same and opposite charge on the bottom. Like charges repel.
They will want to do this again which I always allowed them to do so.

Part II
I pass out the items to test in a particular order with the salt being last. When they recharge their wrap and salt adheres to the wrap, the wrap tears.

Have students charge the wrap and hold it over the small pieces of paper. They will be attracted to the wrap.
Have students charge the wrap and hold it over various sizes of aluminum foil.
Have students charge the wrap and hold it over small bits of rubber and plastic.
Have students charge the wrap and hold over salt. Students enjoyed this the most. Salt is an ionic compound and is very attracted. I liked students to observe that as the charge lessened, the salt began to drop. Recharging the wrap and testing again is good.
Have students recharge the wrap and hold over pencil shavings.

You can choose more items to test. The more ionic a substance is, the greater the reaction. Covalent solids like rubber are not affected by the charge.

Sunday, December 16, 2012

Safety Contract

This is the text of the safety contract I used in the classroom. I had students to sign the contract and take it home for parents to sign. I received the original text to the contract as an employee of Fayette County Board of Education in Fayetteville, GA. United States of America. I may have changed the wording over the years.

What I liked about the contract that it was short and complete.


I will:
1.  Follow all instructions given by the teacher.
2.  Read directions thoroughly before starting an activity.
3.  Protect eyes, face, hands, and body while conducting an                  
     activity.
4.  Know the location of first-aid and firefighting equipment.
5.  Carry out good housekeeping practices.
6.  Conduct myself in a responsible manner at all times in a          
     laboratory situation.
I, ________________________, have read and agree to abide by the safety regulations as set forth above and also any additional printed instructions provided by the teacher and/or district.  I further agree to follow all other written and verbal instructions given in class.  I understand that violation of the Student Safety Contract will result in the suspension of my lab privileges for whatever amount of time is deemed necessary by the teacher.

Magnetic Attraction




First:  Create plastic bags with various everyday items. 

Small pieces of paper, electrical cords with copper wire exposed, hair clips, rubber bands, nails, plastic, sea shells, paperclips, pencils, crayons, aluminum foil, coins and whatever you find that would make the activity interesting.

Magnets are attracted to irons, nickel and cobalt. Alloys of some of these metals such as some steels are attracted to magnets. A good example of a mixture are the plastic strips that adhere to a refrigerator. A magnetizable powder is mixed with vinyl to create these. 

Second: Pass out magnets and plastic bags with items for students to test.

Students can record their data on a table like the one below. Or you could place the table on the whiteboard or bulletin board for the class to record their results.



Remove each item from the plastic bag and test each one with the bar magnet.  Items attracted to the magnet will stick to the magnet. Record your results on the table below. 
Attracted to the magnet
No attraction to the magnet

















Magnet facts
v Items attracted to a magnet contain iron, nickel or cobalt.

v A magnet is strongest at the poles.

v Like poles of a magnet will repel.  Unlike poles of a magnet will attract.

v The Earth is a giant magnet.   The Sun and Jupiter also have a magnetic field.


Extra activity for the SUPER learner!
Take two ring magnets and slide them over a pencil.   Observe what happens.   Take the top magnet off, flip the magnet over, and slide the magnet back on the pencil.   Observe what happens.

Friday, December 14, 2012

Seven Steps to a Stupendous Science Project

Note: I said Stupendous not Stupid.


What is a science fair project? A Model, a collection or an experiment are the three types of projects.



A model is ideal for an elementary student. In all fairness, models are used by scientists to represent objects too small, too large, too expensive or unobtainable to work with. Watson and Crick cracked the molecular structure of DNA with a model. Models are not to be dismissed. However, the average model made by students do not use what is called higher order thinking. This is why it is still suitable for an elementary student but not a high school student.
Volcano erupting on Montserrat 

Models made may be
1. plant or animal cells
2. isotopes or atom structure
3. solar system
4. mature versus young river systems
5. the ever popular "Volcano"


Scientifically, a model as well as careful observation and description of objects is very relevant.

Being able to note slight variations that enable classification is the hallmark of creating collections and organizing information.

Examples of collections would be
1. leaves
2. insects
3. sea shells
4. rocks


An experiment is usually requested as a science project because it demonstrates an understanding of the Scientific Method. 


The Scientific Method is no small concept in that it revolutionized the world and how it processed information. The scientific method is essentially the reason why we know the Sun and not the Earth is the center of the solar system, many diseases are caused by germs, traits of offspring are inherited from parents and horsehair does not turn into worms when it rains. The scientific method essentially says, prove it to me and prove it to me over and over. The scientific method can be summed up in seven steps.

Seven Steps of the Scientific Method.


STEP 1: STATE YOUR PROBLEM


Sample Experiment: Which brand of Chocolate Chip Cookie has the most chocolate chips?




This is actually the hardest part of a science fair project. Developing an experiment. As a judge, a learner, an observer, how interesting is a project in which you know the outcome.

The following is one of the most overdone projects. It entails the purchase of two plants. One plant is treated normal and the other plant is either deprived of light or water or poisoned with salt or sugar. What makes this experiment such a poor choice is two fold.
1. Who cares. Everyone knows the answer. The creator really does not care about their work, they just want to get it done.
2. Two plants are not enough to prove or disprove anything. You need to repeat an experiment several times and have several plants to remove the possibility of a fluke or coincidence.

Take your time. Think about what you are really interested in. When I went to a state Science Fair in Georgia, the rural students had very good projects. The students I accompanied where from a suburb of Atlanta and they were surprised such small town kids did so well. What the rural students did was have very practical observations. For example, one students explored why algae did not grow on a tin roof. One of the students I accompanied did an experiment where they tested how plants grew without gravity. Both were good projects to be there. The one that related to everyday concerns won.

Another consideration, how many people are doing the same project. If 12 students do the same project, their project does not stand out as well. You better make the project incredibly attractive to make a judge want to pick your project. You also have to do every step exceedingly well.

Now you have read and read and you still can't think of an experiment. Pick a subject area you are interested in. Perhaps you will have a question yourself. A big part of creativity is giving yourself time to think. Many people think, I'm not creative. Well creativity is not done like a quiz game at school where speed of answer is at issue. Creativity is giving yourself time to think. Mow grass, do chores, it will come to you.

Depending on your age, you might use a book of proposed experiments. Once you get to high school, you need to be thinking in terms of what would be a great experiment. It is still OK to choose your experiment from a resource. As you study science you will find areas you want to explore more.

You could build your own computer which would be a model. You could compare brands of ports or processor chips which changes your project into an experiment.. The big drawback to this experiment would be the expense. You could take discarded computers to rebuild a computer. You could take computers that are beyond salvage and compare their power supply or motherboard with their computing capacity.

Cost is an issue. Real scientist take into account how much an experiment will cost. The student who did the anti-gravity experiment ran the family electric bill up $200 more the month he did the experiment. If a science project is good, it will be good regardless of how little it cost to do.


It's the process that you are demonstrating. When I went to college, I was so thrilled. No homework was assigned. Then the real discovery was I found myself creating homework so I could do well on the tests. When I was stumped, I had to go to the professor before or after class or sometimes during class if they took questions. The same is true with scientific discovery. The ability will come.



Last but not least, State your problem in the form of a question.

STEP 2:  RESEARCH THE PROBLEM



While researching the problem which brand of chocolate chip cookies has the most chips, I browse the cookie aisle of the grocery store. I looked at the size of the cookie on the package, I count the chips on the cookie shown, I look at the calories per cookie, I estimate the weight of each cookie, I look at the fat grams. Fat grams you say. Of course, chocolate is cocoa butter, cocoa and sugar. The most fat, possibly the more chips. That type of knowledge can come from the library or say your mom. Discussing the problem with knowledgeable people can give you clues on how to approach your problem.

Researching your problem also indicates whether your problem is a good one to tackle or perhaps you should think of another problem. Look at whether you can obtain the supplies needed to do the experiment. Examine the cost. Do you have a good area to do the project. If you do the project in the dead of winter, you cannot choose a project which only works when it is 90 degrees Fahrenheit or 32 degrees Celsius outside. Real scientist are practical.

Why would you choose packaged goods versus Aunt Sue's or Cousin Meggie's to compare. Aunt Sue and Cousin Meggie are not going to make enough cookies to satisfy whoever has a whim for their cookies. Plus they probably vary their recipe depending on what is on hand. Your experiment needs to be duplicated by other scientists.


STEP 3: FORM AN HYPOTHESIS

Make a prediction as to what the answer to your question will be. An hypothesis is a statement that can be tested not an opinion.
Write down the answer to the question you originally posed. This is called your hypothesis. An hypothesis is defined as a scientific guess, educated guess or most recently a testable explanation for a problem.
My hypothesis is that brand X will have more chocolate chips per cookie than brand Y. I decided this because brand X has more fat grams and the picture on the package has 23 visible chips and brand Z has 12 visible chips.

STEP 4: DESIGN AN EXPERIMENT TO TEST YOUR HYPOTHESIS

When creating an experiment, you are comparing two factors that are identical except one factor has been changed. The factor you change is called the variable. It is also called your independent variable. All conditions between the two trials must be identical or as close as possible. You keep notes as to what could not be kept the same. The variables that do not change are noted and called controlled variables.

Perhaps the experiement of "Which brand of chocolate chip cookie has the most chips?" has controlled variables as being done at the same temperature, the same scientist, the same speed of experimentation, the same light level.
The variable that may differ are the size of the cookie or size of the chip.

The experiment may be conducted by taking a cookie from each brand and breaking up the cookie and counting the amount of chocolate chips. You need some sort of measurement or observation not an opinion. An opinion would be it seemed to shake. You need something quantifiable which means measured. It vibrated 2 cm in each direction for 20 seconds would be a measurement.

Stating that one object is prettier than another is a value judgement and cannot be measured. However description of a smell as unpleasant or pleasant would be a valid observation.

STEP 5: COLLECT DATA




A chart or table is preferable. A great deal of information can be stored in a logical easy to find format.

Scientist go for the practical and expedient. A great riff of a guitar is art. When you write excessively, it is difficult to read. Even poets, novelist, journalist write only what is necessary to tell their story. Anything extra distracts from what is told.

This is the fun part of an experiment. You may have to conduct your experiment over a period of several days. What you will have to do is conduct the experiment several times. In order for results to be valid, you must get similar results over and over.

STEP 6: FORM A CONCLUSION


State whether the hypothesis was proven or proved wrong.

In addition, you should discuss factors that affected your experiment. How could these have affected the results. This is good area to propose variations of the experiment to get better results.



STEP 7: PUBLISH



Essentially this is what your science project display is all about. Your teacher will give specific guidelines for the science fair.

Remember, keep it attractive. Attractive projects score better than the science behind them. Go into a store, products are placed in packages designed to make you want them. Impulse items are on corners or eye level. Why do you think they put candy, gum, soft drinks, nuts and magazines at the checkout counter of a grocery.










Tuesday, December 11, 2012

Demonstrating that molecules of warm water moves faster than those of cold water.

You need two identical transparent containers. Put cold water in one container. Put the identical amount of warm water in the other. Place drops of food coloring in the cold water. Then put drops of food coloring in the warm.

Even with the addition of food coloring in the warm later than the cold water, you can witness the food coloring slowly dispersing in the cold water and quickly spreading in the warm water. This is a good demonstration.

Question: What causes the food coloring to spread through the water without stirring or shaking?
Answer: The movement of the water molecules

Question: Why does the food coloring mix faster in the warmer water?
Answer: The warmer the molecules are the faster they move. The quicker movement disperses the food coloring throughout faster.

Monday, December 10, 2012

Layers of the Atmosphere Activity

Any textbook in your classroom should give most of the information for the activity. If there is a fact or two missing, you could supply a short supplementary text or the fact to the students.

What surprised me the most when I did this activity was the high test scores. I did not lecture, give notes, go over review questions. The activity was it.

I grouped students in groups of three and four. I selected groups. I deliberately mixed high ability, low ability and average in every group.

Each group was given an approximately 3 ft by 3 ft piece of butcher paper  (The white paper use to cover bulletin boards). Any poster sized paper would do. In a pinch 11 X 17 copy paper can be used. I would just expect students to work in groups and make an individual drawing.

The activity was done with a sixth grade classroom. I gave students the instructions and rubric being used to grade them.

For this rubric, emphasizing that each component was completed was important versus quality of drawing issues. I would voluntarily start grading the project when asked and put a big X where the information was missing then sum the grade. Even though the project was attractive, children were surprised they had a 60 because they had not listed all the facts. This helped guide them to get all the necessary facts on their diagrams for the real grade.

I did separate the A's from the B projects by presentation. I also did not give students another sheet of paper to start over. We all work on a deadline. Letting them start over and over will cause some students to take extraordinary extra time or never complete the project. It also helps teach students to think ahead. Since you grade on whether a fact is listed, an incomplete project can be graded.

I also allowed students to borrow large circles found around the room to draw their atmospheric layers. I did not encourage this in that I would tell students that the layers blend together and do not have neat divisions between them.

I never marked students down for poor art skills. There is a difference between rushed, sloppy work and poor motor skills.  I never had a child challenge me with my grades in comparing their work with another.

Instructions:

You will need to make a diagram on this poster to demonstrate the information assessed in the following rubric. Use your textbook or the text supplied to find this information. I suggest you find the information and plan before you begin to draw. You will not be supplied another piece of paper.


Atmospheric layers Rubric                  

Group members ______________ ______________ ______________


Quality
possible points
self
assessment
earned points
1.  Label Earth
5


2.  Five layers labeled
5


3.  Distance from Earth of each layer
5


4. Temperature range of each layer
5


5.  Facts placed in appropriate layer



- layer in which we live
5


- layer in which all weather occurs
5


- ozone layer is found here
5


- coldest layer
5


- hottest layer
5


- ionosphere is found here
5


- meteors occur here
5


- blends in with outer space
5


-space shuttle and satellites found here
5


6.  Illustrations



- Earth
5


- Weather
5


- show ozone layer blocking ultraviolet light
5


- hottest layer
5


- space shuttles and satellites
5


7.  Effort
5


8.   Neatness
5


9.   Total points
100