Comparison

Number Line, by MLC vs Playground Physics

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Number Line, by MLC

This app allows students to visualize number sequences and demonstrate mathematical strategies. It supports various number types and offers tools for annotation, problem-solving, and sharing work. Ideal for elementary classrooms and iPad learning environments.

Highlights
  • Visualize number sequences
  • Demonstrate counting, adding, subtracting, multiplying, dividing
  • Use whole numbers, fractions, decimals, or negative numbers
  • Add custom tick marks and labels
  • Hide and reveal numbers and jumps
  • Annotation and drawing tools
  • Save and share work
Features
Read full description

Number Line helps students visualize number sequences and demonstrate strategies for counting, comparing, adding, subtracting, multiplying, and dividing. Choose number lines labelled with whole numbers, fractions, decimals, or negative numbers. Or use a blank number line, with or without tick marks. Describe intervals between points on the line using forward or backward jumps above and below the line. Jumps can be labelled with their values or left blank. Add custom tick marks to the number line to show equivalence or compare number values. Show strategies with drawing and annotation tools. Hide elements of the sequence shown on the number line, which challenges students to use what they know about number relationships and computation to identify those missing elements. This virtual number line is an open-ended educational tool, ideal for elementary classrooms and other learning environments that use iPads. For more Number Line resources and other apps, visit: www.mathlearningcenter.org/apps FEATURES • Mark the number line with multiples of whole numbers, fractions, or decimals. In addition, set the starting value of the line, including using negative values. • Add and manipulate forward and backward jumps, above or below the line. • Label jump bars, manually or automatically, to show intervals or hide labels altogether. • Add custom tick marks and values to blank number lines. • Hide and reveal numbers on the number line. • Hide and reveal jumps, numbers, and other elements with resizable covers to create your own problems and model strategies. • Use the drawing tools to annotate work and show understanding. • Add equations, expressions, and descriptions with the math text and writing tools. • Share your work by saving an image or providing a share code to others. MORE APPS For more Number Line resources and other apps, visit: www.mathlearningcenter.org/apps LEARN MORE To learn about Bridges in Mathematics, an elementary curriculum that employs visual models like number line, visit: www.mathlearningcenter.org/bridges/overview ABOUT US This resource is brought to you by The Math Learning Center, a nonprofit organization dedicated to K-12 education since 1976. ACKNOWLEDGEMENTS This app was crafted by Clarity Innovations. We help improve teaching and learning by creating solutions that match promising technologies with the needs of education. Visit us: www.clarity-innovations.com

About

Playground Physics

Record videos of motion, trace paths, and analyze physics concepts like forces and energy. This tool helps educators bring Newton's Laws to life with interactive graphs and slow-motion playback. Ideal for middle and high school science.

Highlights
  • Record and analyze motion in videos
  • Trace paths and examine movement
  • Interactive scrubbable graphs
  • Slow-motion playback
  • Calculate forces and energy
  • Save and share performance videos
Read full description

Discover and explore the physics in your own movements. Record a video of you or your friends, tap points along the way to trace a path of motion, and discover the motion, forces, and energy involved. Educators can make Newton’s Laws of motion come alive with an app that was named one of Fast Company’s Top 10 mobile apps! Join a community of educators making inspiring learning experiences with Noticing Tools. “Playground Physics is one of the most fun units that I’ve done in a long time. I’ve been teaching about 12 years, and everybody had a great time.” - Stacey, 8th grade science teacher In Playground Physics, you can: * Record a video of a performance or choose a stock video. * Tap points along the video to trace a path of motion. * Examine your performance closely with scrubbing video controls. * Enter known measurements (height of an object, mass of the object being tracked) in English or metric units to reveal accurate data of your performance. * Explore interactive, scrubbable graphs synchronized to the video playback. Graphs display the distance traveled and speed along the path in horizontal and vertical vectors. * Add stickers to mark important moments in the performance (and for a laugh!). * Play your video back in slow motion to closely examine your movements. * Explore how distance, speed, and direction changes when things move. * Understand how a person's or object's potential and kinetic energy change as they move. * Save your performance as videos with data overlays or editable scenes. * Share your performance videos or transfer editable scenes to other cloud services and apps through use of the Files app. Ideal for middle and high school school science classrooms, Playground Physics and accompanying curriculum activities are aligned to and embody the Next Generation Science Standards (NGSS) by integrating core ideas, scientific practices, cross-cutting concepts, and delight! The new 2023 edition of the curriculum is freely available at: https://noticing.nysci.org/apps/playground-physics/ Playground Physics is one of the Noticing Tools (TM) from the New York Hall of Science. The full suite includes Choreo Graph, Fraction Mash, Size Wise, Volumize, and Picture Dots. Noticing Tools were developed in collaboration with Local Projects, an award-winning media design firm based in New York. http://localprojects.com/

Verdict

The call

Number Line, by MLC and Playground Physics both sit at 4.4 stars, but that hides the real split: 67% of Number Line, by MLC's written reviews are positive against 40% of Playground Physics's. Number Line, by MLC also leads on ratings volume (15 vs 5). Playground Physics's advantage is update cadence (every 5 months vs every 13 months). On price, rating, ads and in-app purchases there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Playground Physics holds the better App Store score, 4.6 against 4.4. Both are backed by a comparable volume of ratings — 15 and 5 respectively. Written reviews complicate that: 67% of Number Line, by MLC's written reviews are positive against 40% of Playground Physics's, so the app with the better star average is not the one people write more warmly about.

UpkeepUpdate frequency

Number Line, by MLC ships an update every 13 months, Playground Physics every 5 months. The most recent releases landed on November 6, 2026 and November 1, 2026 respectively.

Scorecard3 real differences · 7 level
Number Line, by MLC versus Playground Physics: the parameters behind the verdict, then further details
ParameterNumber Line, by MLCPlayground Physics
PriceFreeFree
Rating4.4 (15 ratings)4.6 (5 ratings) — better
Positive reviews66.7% of reviews — better40.0% of reviews
Number of ratings15 — better5
Update frequencyEvery 13 monthsEvery 5 months — better
AdsNoNo
In-app purchasesNoNo
MonetizationFreeFree
DevicesiPadiPad
Requires iOS16.115.0 — better
Further details — not scored
Size7 MB45 MB
Age rating4+4+
DeveloperThe Math Learning CenterNew York Hall of Science

Customer experience

Number Line, by MLC

All ratings15 ratings
Positive86.7%
Neutral0.0%
Negative13.3%
Written reviews12 reviews
Positive66.7%
Neutral16.7%
Negative16.7%

Playground Physics

All ratings5 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews15 reviews
Positive40.0%
Neutral6.7%
Negative53.3%

In-app purchases

None

Number Line, by MLC

No in-app purchases

None

Playground Physics

No in-app purchases

Questions

Is Number Line, by MLC free?
Number Line, by MLC is free to download, with no in-app purchases.
Is Playground Physics free?
Playground Physics is free to download, with no in-app purchases.
Which has better reviews, Number Line, by MLC or Playground Physics?
Playground Physics is rated higher. Number Line, by MLC averages 4.4 out of 5 from 15 ratings, while Playground Physics averages 4.6 from 5 ratings.
Do Number Line, by MLC or Playground Physics have ads?
Neither Number Line, by MLC nor Playground Physics shows ads.
Which is updated more often, Number Line, by MLC or Playground Physics?
Number Line, by MLC ships an update every 13 months, and Playground Physics every 5 months. Most recently, Number Line, by MLC was updated on November 6, 2026 and Playground Physics on November 1, 2026.

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