## Saturday, September 3, 2016

### Rounding

Rounding is a concept that many of my kids really struggle with.  A teacher friend shared this idea with me.  Tell students they are shipwrecked on an island.  This island doesn't have anything on it.  However, there is another island nearby that has lots of delicious fruit trees.  There are 9 stones connecting the two islands.  Student 1 decides to jump across the stones to get to the other island.  He jumps on the first stone, but before he can go any further, a huge wave comes.  Ask the student, "Are you going to jump back to the island of nothing, or jump ahead to the island of plenty?"  Student 1 is going to jump back because he is closer to the island of nothing.  Continue this process with a student making it one stone further each time.  When the 5th student jumps to stone 5 ask, "You are exactly in the middle of the two islands.  Are you going to jump back or jump forward to avoid the wave?"  Students should answer forward because if they are half way, why not go forward to where the food is?

Then we related this to numbers.  I gave the students a number such as 52.  I explained that 52 was between 50 (island of nothing) and 60 (island of plenty.)  They were on the 2nd stone.  Which way are they going to jump if the wave came?  This strategy helped my kids see why we round the way we do.  It was so much easier for them then to try to remember some little poem.  I hope this helps your little ones with rounding.  Best of luck this year!
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