2nd Grade Number Sense Resources
A random number of objects (between 0 and the upper limit you specify) flashes on the screen. Estimate how many you saw. Then display the picture again, reconsider your guess, and finally see the answer. Designed to develop solid connection between a number and how "big" it actually is.
An updated version of "How Many?" with a new feature: once you see the squares, you can arrange them into groups. Use this to connect estimation and quantity to skip counting. Or use it to have a conversation about multiplication or division.
This grid goes to 120. Click on the numbers to toggle the colors. Click on an arrow to turn the entire row or column red. Explore 1 or 10 more/less, patterns in skip counting or beyond.
Meant to help develop the idea of possible rounding outcomes by exploring the numbers on an interval of 10, 100, or 1000. Name numbers on an interval (and predict their location!) or drag a randomly generated number to the correct spot (with feedback on the placement provided).
Enter a whole number (under 1 million) and it will be shown as a bar partitioned along base-10 values. Use this for a visual demonstration of, for example, why 543 > 345, beyond "because 5 is bigger than 3".
Drag whole numbers to the correct locations on a (mostly) blank number line. Feedback provided. Adjust the upper limit for the size of the number and how many are placed on the line.
Enter a number (up to 1000), then regroup it into ones, tens, and hundreds. See also "Making Tens." Designed to allow students to see lots of equivalent representations of numbers.