• best teaching practices
  • The problem with “5 or more go next door”

    We’ve seen the cute roller coaster rounding poster but does this really teach our students how to round? Once again, we must take the time to teach students why.

    Why do we ‘round up’ when a number is 5 or more?

    How can we teach rounding effectively? By using number lines.
    By teaching students to use number lines, we can help them see why ‘5 or more round up’ while ‘4 or less round down’. Number lines show the distance for a number that is 5 or more is closer to the next number while the a number that is ‘4 or less’ is closer to the number prior.

    Rounding 78 to the nearest tens –> 78
    78 is 8 away from 70 while only two away from 80. So when rounding to the tens place, 78 rounds to 80 because it is at a closer distance than 70.

    Rounding 326 to the nearest tens –> 326
    326 is 6 away from 320 while only 4 away from 330. So when rounding to the nearest tens place, 326 rounds to 330 because it is at a closer distance.

    Rounding 2,334 to the nearest hundreds –> 2,334
    2,334 rounds to 2,300 because it is at a closer distance than 2,400.


    This video definitely proves just how important talking is in the classroom. It is super super super important for students to be having conversations with one another while practicing simple math skills. Students constantly need to be exposed to and practice using correct math vocabulary!! Teachers also have such an important role in providing not only the atmosphere for this, but to also be modeling while they teach! Also, it is vital for teachers to remember to use their questioning skills 🙂

    Some sentence stems you and your students should be using when rounding.

    • “We can draw a number line to show this”
    • “# is between # and #”
    • “# is more than or less than #, therefore it is closer to #”
    • “# rounds to # because it is closer than #”

    Want more suggestions, tips, and rounding practice? Here is a link to a rounding bundle.

    How do you help students better understand rounding?