Join the beta

Curriculum › Math ›Grade 2

Grade 2 Math · Level 4, Arithmetic within 100

Approximation / Nearest Number

Decide which benchmark a number is closest to and judge whether an answer is reasonable.

Questions like

  • Is 73 closer to 70 or 80?

How the lesson starts: Approximation / Nearest Number

  1. Freddy the frog

    Ribbit! Meet Freddy the frog. He's sitting on stone 73. Lily pads float at 70 and 80. Freddy wants the closest lily pad. Which one?

  2. Count the hops

    Here's the pond. Freddy sits on 73. Hopping back to 70 takes 3 hops. Hopping ahead to 80 takes 7 hops. 3 is less than 7. So 73 is closer to 70!

  3. Let's try 86

    Is 86 closer to 80 or 90? From 80 to 86 is 6 hops. From 86 to 90 is 4 hops. 4 is less than 6. So 86 is closer to 90!