Number Line Hops
Show addition, subtraction and skip counting as jumps along a number line, with whole numbers, negatives or decimals.
How to use it
Choose whole numbers or tenths and set the ends of the line (negatives are fine). Pick a start, an operation and a jump size, then press Hop! The hops are drawn one at a time and the matching equation is written above the line. Skip counting makes several equal hops, the way you count by 2s, 5s or 0.5s.
The two challenges use the line you set. In where does it land? you see the start and the jump and type the landing number. In what jump was made? you see where it started and stopped and type the jump with its direction, such as +6 or −3.
The math: adding moves right, subtracting moves left
A number line puts every number in order, evenly spaced. Adding a positive number is a hop to the right; subtracting is a hop to the left. The length of the hop is the same wherever it starts, so 3 + 4 and 13 + 4 are the same-sized jump. Skip counting is repeated addition: four hops of 5 from 0 lands on 20, which is also 4 × 5.
Below zero the same rules hold. Starting at 2 and subtracting 5 crosses zero and lands on −3, like a thermometer dropping 5 degrees from 2 °C. With tenths, each whole is cut into ten equal steps, so 1.7 + 0.5 lands on 2.2.
- Start at −4 and add 6. Where do you land? What temperature story could this be?
- Count down by 3 from 20. Do you land on 0? Why or why not?
- Which is further from 0: −7 or 5?
Free to use, no account needed. It runs in your browser: nothing you type, and no sound from your microphone, is sent to Fieldbook.
Hands-on lessons to pair with Number Line Hops
Ready-to-teach units, each lesson a printable teacher guide and student sheet. Your first three lessons are free.
Measure It: Length, Time and Mass in the Real World
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Why tires go soft in winter, why sidewalks have gaps, and how a thermometer knows. Five lessons on what heating and cooling do to the particles in everything around us.
Weather Detectives
Warm winter winds, the hottest spot in the schoolyard and the last frost of spring. Students measure weather fairly and find out why farmers care so much about it.
Three full lessons, free
Make a free account and download any three Fieldbook lessons, from any grade or subject, as printable PDFs. No card needed.
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