Estimation in the real world

When it comes to estimation, you need to be careful when close enough is good enough.  When balancing a checkbook you need to be spot on.  When estimating what your total for your grocery bill is, that however can be close enough.  Rounding to the nearest dollar should suffice.  I always feel better rounding up than rounding down.
For an example, I have $50 to spend on grocery's for the week.  I go down my list and put the price, estimated to the nearest dollar.
Bread 2.00
Lunchmeat 4.00/lb
Noodles 1.00
Lettuce 2.00
etc, etc....  I add up the total and then minus my coupons.  Coupons are a must these days!!
This is a wonderful real-life lesson for your children as well.  They can have their own notebook and do the estimating and see how close they are at the end.

Estimation can be done in a variety of situations.  It is a great help when time is of the essence and an exact is not needed. Estimation can be done, with time such as how long will it take to grocery shop?  It can also be done with size, is it worth getting the economy pack of hot dogs?  Will they all get eaten?



Adapting this to your classroom can be very easy.  For younger grades you can have students bring in empty food containers and set up a grocery store.  This activity was done by the preschool teacher that I worked with two years ago, the students loved it.  There also is a pretend grocery store at the Minnesota Children's museum and that area was packed every time we visited.  Everything can be priced and have play money with a cash register, I guarantee they will love it.


For older students they could bring in ads from the local grocery stores and with a budget amount do their shopping.

  More or LessPlace eight quarters in a row. Replace every other coin with a dime. Replace every third coin with a nickel. Finally, replace every fourth coin with a penny. What is the value of the eight coins now? How much more or less money do you have than when you started? Were any coins not replaced? Why or why not?

From Math by the Month, May 2001 TCM. - See more at: http://www.nctm.org/resources/archive.aspx?id=3604&journalid=4#sthash.9ZhTjIwK.dpuf

  More or LessPlace eight quarters in a row. Replace every other coin with a dime. Replace every third coin with a nickel. Finally, replace every fourth coin with a penny. What is the value of the eight coins now? How much more or less money do you have than when you started? Were any coins not replaced? Why or why not?

From Math by the Month, May 2001 TCM. - See more at: http://www.nctm.org/resources/archive.aspx?id=3604&journalid=4#sthash.9ZhTjIwK.dpuf

This website is a great place to start for math at the grocery store.  Take a look around.


 

Will I ever really use this???

When are we ever really going to use this?????

This is one of my biggest pet peeves.  Math is everywhere all of the time!! 

So, yes my answer is yes.  You will use this, whether you know it or not!


 


I gave my son three dollars to go buy water at the Renaissance Festival last year.  He came back with $.50 and a bottle of water.  My reaction?  “Holy $2.00 for a bottle of water, crazy!”  He just looked at me and said, “No, mom it was $1.50”  Well, come to find out Evan knew that she owed him another dollar but didn’t have enough courage to ask for it.  Of course being the outspoken person I am we went back to the stand and asked for our dollar.  She looked a little sheepish knowing that she was trying to take advantage of an 8 year old.  This brings me to my point of knowing math and being able to know how much money that you get back when making a purchase.

When my sons and I go grocery shopping we figure out the best deals.  We compare price and size.  I make it a game and they think of it as a challenge.  Children need to know how to add the cost of items and subtract from the budget amount.  This is a life long skill that everyone should know.  They also need to know when there is something special that they want to buy, how much money they need and what chores they have to do to get it.

 According to the Minnesota State Standards Strand 3 Geometry and Measurement, the standard 3.3.3.3 states, "Use time, money, temperature to solve real-world mathematical problems." The benchmark states, "Make change up to one dollar in several different ways, including with a few coins as possible."

http://education.state.mn.us/MDE/EdExc/StanCurri/K-12AcademicStandards/

I found a few math games online that deal with money that will be good practice for your child.