More Fluid Dynamics in the Bath Tab

A few nights ago my son and I enjoyed playing around with these water buckets in the bath tub.  Simply watching the water stream out of the little holes at the bottom of the bucket is entertaining.  As the water level inside the bucket decreases, the speed of the water coming out of the holes, and the distance it travels decrease.  The proportional relationship requires some real algebra skills to quantitatively describe, but we could see it pretty easily.  The less gravity can push down on the water in the bucket, the less the water coming out of the holes is accelerated.

Here is another fun little experiment.  Push the empty bucket down into the water and watch it fill up.  How high will the water level inside go?    Since there is more water outside the bucket than inside the bucket, there is more gravity pulling down on the water outside the bucket.  This tempts many people to believe that the bucket will fill up higher than the surrounding water.
However, the water is a fluid, which means that it is affected by pressure.  Pressure increases when force increases and decreases when effected area increases.  The bucket will fill only until the inner and outer pressures are equal.  Since the inner surface area is smaller, the same pressure can be reached with less water.




So what about those demos that show the bottled filled with water above the water line?  We didn't play with those, so I will have to save it for another post.  I will say, that the different results demonstrate why I think it is really important that we spend time playing around with the typical every day world.   We need to fully appreciate the every day events before we can really enjoy the special cases--and that's exactly what we did.


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Circular Motion at the Breakfast Table

Circular Motion at the Breakfast Table

One morning my son began amusing himself by rolling the peanut butter lid across the breakfast table.  Of course, little sister wanted in on the fun, so we retrieved the orange juice lid as well.

The orange juice lid did something new.  It rolled in a circle.  

When I asked my kids why the peanut butter lid was traveling in a straight line, while the orange juice lid traveled in a circle, my son was able to tell me that it was because the outside rim of the orange juice lid is longer than the inside rim.

He was right!  As a solid object, the entire lid must maintain the same angular speed.  Every molecule revolves around the center at the same speed.  For the peanut butter lid, which has a uniform circumference, that means that all parts of the lid travel at the same linear speed as well.  However, for the orange juice lid, the smaller circumference on the inside means that a smaller linear distance will be traveled on the inside of the lid during each rotation.  In order for a solid object, like the lid, to travel a smaller linear distance on one side than the other, it has to travel in a circle. 

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Summer Rainbows

Learning Newton's Second Law from the Garden Hose

Science teacher link up!

I was very excited to find this great link up for science teachers.  If you blog about teaching science, please join!

Library Treasures: I Columbus, My Journal

Today, I found in the children's section of our library, a copy of Christopher Columbus's journal of his first trip to the Americas.  Fortunately for my four-year-old and me, Robert H. Fuson translated Columbus's memoir into modern day English.  This book was edited by Peter and Connie Roop.  It is no surprise to learn that they are both accomplished teachers.

What does surprise me is that this work was never required reading for me.  It will not need to be required reading for my son.  We finished the whole thing this afternoon.  Several times, he urged me to keep reading.  When land was sighted, he literally jumped up and started clapping.  He was especially captivated by the illustrations, done by Peter E. Hanson.  At this point, he does understand that Columbus's venture was a key event in the history of what was to become our country, although he misses the philosophical shading of the memoir.  When he is ready to consider the more nuanced cultural and historical implications of the migration of Europeans to the Americas, this would be a perfect starting point.

Typically, I add the books I find in the library to my wish lists, but I  I, Columbus: My Journal went straight to my cart.  It is definitely a book I want to read, and to encourage my children to read again.

Training that sticks

My kids are taking swimming lessons this week.  They seem to be having fun.  The teenagers running the local program are enthusiastic and competent.  I have just one complaint.  One little girl has screamed at the top of her lungs for forty-five minutes, two days in a row.  I do not fault the teachers.  I do fault her mother.  Why would you EVER let your child scream in horror in the arms of  stranger for all that time?  Do you really think she is going to learn to be a great swimmer because you insisted on her completing this task to her absolute objection now?

As a side note, if you you are thinking of swimming lessons, I would highly recommend that you personally take the time to help your child feel comfortable holding on to the side of the pool, in a depth over their head, and happily dunk themselves under water on command before you take them to class.  This did involve some bribing in our case, but now both children love to go under water.  We also invested in some goggles.  

I was, and continue to be, frustrated by the mom who sits insistently by while her daughter mourns the expectations.  Then I realized that I was her.   After we arrived home and ate lunch, we commenced our morning "responsibilities" which we had missed due to the swimming lessons.  I found myself rushing my children, insisting that they finish putting away the dishes and laundry now.  They began to object, and I steeled my resolve.  Then, I realized: I am no better than the mom at the pool.  My goal for my kids was a good one, but my method of obtaining it was not.  Is there a reasons they must hurry?  Why can't putting the dishes away be fun? So, when my son asked where the bowls go (as if he doesn't know!), I responded with, "Under your pillow."  He laughed.  "With the plates?"  More laughter, "With the bowls?"  And it was done.  

Having fun took longer. If I wanted the work done quickly, should I not just do it myself?  If my objective is to help my children learn to see responsibility as a joy, I should do what I can to make chore time a happy time.

 I am looking for suggestions.  How do you make chore time fun for yourself or for your kids?

Summer Rainbows

When my sister and I were little girls, my mother would sometimes let us play with the hose in the back yard.  One of our favorite games, well, one of my favorite games was to walk down the rainbow.  One of us would hold the hose and direct the other to walk either to the right or the left as needed to walk down the rainbow created by the hose.  I was mesmerized by the sight of my sister running down a rainbow.

This summer my own kids have been interested in rainbows created by our hose, and by the sprinklers in our neighborhood.  (For those of you crying out in horror at the sight of sprinklers going off in broad day light, it's all determined by the HOA.   So much for a water shortage.)

But, Why Mommy, Why?

The sun's radiation comes into the earth's atmosphere at all visible wavelengths, and some non-visible wave lengths as well.  When you have an even dispersion of all colors of light, the effect is blindingly white.  As light travels through water, it is slowed.  Different colors of light are slowed at different rates, depending on their wavelengths.   That is why the white rays that entered the spray of water together, leave at different angles separated neatly by color.   In pre-school language, when you bend light, the colors come out. Your clap-able word of the day is diffraction: the bending of waves.

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Guest Post: 10 Simple Ideas to Get Your Kids Outside

As a secondary science teacher, one of my top three frustrations was my students' lack of real, physical world experience. Today, I am excited to bring you a guest post by my good friend Summer about getting kids involved in the world outdoors.  You will want to check out her blog Outside Kid for some fantastic project ideas.

“Boys, go outside!”

“No, we don’t want to,” my four year old protests. “We want to stay inside and watch a movie.”

“Movies are boring! It’s a beautiful day! Go outside and play!”

“Nah. Can I watch Shaun the Sheep?”

Ever had a conversation like this with your child? I have had more than I’d like to admit. I thought all kids preferred to be outside. What’s wrong with mine, I wondered?  Well, as it turns out, nothing! I just haven’t been creating the right atmosphere for young children to enjoy the great outdoors. Recently I decided to commit myself to being an outside mom, so I can have outside kids. It’s important to me to stimulate their little brains, introduce adventures, and encourage creativity.

So, for any mom who has ever pleaded with their little ones to get some Vitamin D, here are 10 simple ideas to encourage your children to spend more time outside.

1.  Go outside with them. I know you know this. All little kids want to be in the same place Mommy is. So, if Mom is outside, the children will follow. The housework can wait.  

2.  Institute a No TV Day. We started doing this a while back and it’s amazing how quickly the kids just accepted it. My oldest will ask me most days, “Mom, is it a No TV Day?” We usually have about one day a week where we keep the television off and the kids are forced to find other activities.

3.  Make certain activities outside only, like coloring or eating snacks. This started because we’re in a rental house and my 2 year old got a hold of the crayons and drew on the wall. My husband banished all drawing to the outside. I protested at first, but again, the kids took to it quickly and now if they want to color they just do it outside on their little table. (Obviously this is weather permitting!) Also, they know that most of their snacks they eat outside at their little table, or they roam around in the backyard with a “snack in a bag” which is usually cereal, nuts, dried fruit and a few chocolate chips.

4. Hang your laundry. One of the reasons I’ve often told my children that I can’t go outside to play with them is that my biggest chore for a family of 5 is keeping up with the laundry, and it seems to invariably be something I have to do indoors. A great way to solve this problem—and save a chunk on your electric bill—is to hang your clothes. If this is new for you, start small by just hanging your towels and sheets. You can fold outside, too, which also gives your little ones more time in the fresh air with you.

5.  Invest in comfortable outdoor seating. When we go to visit my extended family, we always enjoy breakfast outside on the back patio. Why? Because they have a comfortable patio set and everyone loves to congregate in the backyard. If you don’t have a outdoor set, check out yard sales (a few cans of spray paint can go a long way!) or keep your eyes open for floor model sales toward the end of the summer.

6.  Commit to buying only active toys. My mom has said that kids today don’t play with their toys, they watch their toys play. Isn’t that true? So for birthdays or holidays, buy your children active toys like bikes, tents, basketball hoops, and things that will keep them healthy. The trick? Get toys that you will enjoy playing with them.

7.  Take up gardening or yardwork. This is a great way to spend more time outside and teach your children about how things grow. Plus, you can save some money on healthy organic fruits and veggies!

8.  Schedule outside time in your child’s day, such as right after breakfast or before dinner. If it’s a routine, they’ll quickly accept it and accustom themselves to finding fun things to do.

9.  Invite their friends over. My boys will stay outside for hours when their little buddies come over. All of a sudden our little backyard is transformed into an enormous game of show and tell.

10. Ditch the TV. If you want to get reckless, go whole hog and get rid of it. Or, for a milder option, cancel your cable and subscribe to Netflix. This is what we do, and while you can certainly still watch a lot of programs, at least your children aren’t exposed to commercials and other advertisements, and it’s not as easy to just leave it on all day.

Have any other good suggestions? Leave it in the comments section, or email me at summer@outsidekid.com. Summer is a mama to three great kids ages 4, 2 and 6 months and blogs at www.OutsideKid.com.

Formulating a Master Shopping List: Step One

I am slowly becoming a fan of using multi-step programs to improve one area of my life or another.  My latest favorite is The Granny Plan from Granny's Vital Vittles.  As we have been bouncing around the country, our grocery habits have been rather eccentric.  As we have been settling into our new home, I have also been settling into a routine of grocery shopping and cooking.

The one problem with the "Granny plan" is that Granny did not move nearly as often as we do.  The whole concept of building up a pantry (a key step in the program) is thwarted, when you continually move in a matter of months, rather than years.

So, I thought I would share the system that I have developed over time to help me stream line the store to table process both financially and time wise.  I find it useful to start this process at the beginning every time we move, although pieces of it can be reused.  Ultimately, using this system you can switch over to shopping for staples monthly,  or even less often.  Or, you can plan to start utilizing all the great tricks for purchasing needed goods at the best prices.  Or, you can just be sane and get dinner on the table without stressing about it too much.

Step one:  Write down a list of what you are going to cook for dinner for the next seven days.  

Here are my rules for writing down this week's meal plan.

1.  The complete menu for each dinner is written down--either on a list on the fridge or in my planner.  I can't decide which place I like better

2.  No more than one new recipe may be included in any week's plan.  Cooking new recipes takes more time than cooking things I have already mastered.  This rule keeps me from overwhelming myself.

3.  Repeated meals, purposeful leftovers, frozen pizza, and restaurants are all valid entries on the meal plan.  The point is to plan ahead, so that on a given day you can swing into action rather than using time and energy to make a decision in the moment.   There is plenty of time later for becoming super woman of the kitchen.

That's it.  Go ahead and write yourself a quick meal plan.  Tomorrow, I'll share what I do with my seven day meal-plan.  In the mean time, please share any hints you have on how to write a successful meal-plan.

This post is kind of a mistake.  I meant to be writing on my other blog.  Yes, I was feeling a little tired, and writing is supposed to clear my mind.  If you're interested in this series, please click  here to go over to my other blog and follow along!