From: Gail 
To: Teacher2Teacher Public Discussion
Date: 2000101214:04:02
Subject: Re: Front-end estimation

>When you are using front-end estimation in addition, how many places
do you estimate.
           + 357,289
>
>            238,499
>
>          _________
>
>            500,000
>
>       or   580,000
>
>            595,000




When I teach my fifth graders to use front end estimation, I am trying
to give them a check and easy way to get a "ballpark" answer. So I ask
them to look at a problem like the one you shared above, and think, "3
hundred thousand plus 2 hundred thousand is 5 hundred thousand.  I
have about another hundred thousand if I look at the remainder of the
two numbers, since 57 thousand is almost 60 thousand, and 38 thousand
is almost 40 thousand.  That means the answer is about 600,000.

It is a great way to develop place value number sense, and a very
quick way to find an estimated sum.  Hope this answers your question.

 -Gail, for the Teacher2Teacher service

Post a reply to this message
Post a related public discussion message
Ask Teacher2Teacher a new question