Players drag cards on the two sides of a board to isolate a glowing box, obeying rules such as 'what you add to one side you add to the other'; over the chapters the pictures are replaced by numbers, letters, parentheses and fractions until the board is a written equation.
Why it may be useful
The rules of equation-solving are learned as moves before any notation, so a player who freezes at 'x' can already do the manipulation; classroom studies show hundreds of equations solved happily within a few hours.
Used in teaching
3 documented cases ↓Carnegie Mellon University · Worcester Polytechnic Institute
Keep in mind
Research finds strong engagement but weak transfer to paper equations, and the app now sits behind a subscription or a one-time purchase after a trial.
Written 2026-09-15 · editorial assessment, not a measured effect · how we rate →
What the game is
Kahoot Algebra 2 by DragonBox is a mobile puzzle game first released in 2013 as DragonBox Algebra 12+, made by a Norwegian team and now published by Kahoot. It runs on iPhone, iPad and Android. The official product page gives an age range of nine and up.
A board is split down the middle by a line. On each side sit picture cards, a beetle or a die or a swirl, and one of them is a glowing box. The goal of every level is to leave that box alone on its side of the line. You do it by dragging cards onto each other: a card and its dark twin cancel to a puff of dust, and anything added to one side has to be added to the other.
Nothing is written down at first. Then, chapter by chapter, the pictures are quietly replaced. The beetle becomes a letter. The dividing line becomes an equals sign. By the last chapters the board is a written equation with parentheses and fractions, and the moves a player has been making for hours turn out to be the moves of algebra. The official page lists addition, multiplication, division, parentheses, positive and negative signs, addition of fractions with a common denominator, collecting like terms, factorization and substitution.
What you actually do
You look at the board and decide which card is in the way. Drag a card onto its opposite and both vanish. Drag a card from the deck onto both sides at once to cancel something that cannot be removed directly. Drop a card onto the dividing line and it becomes a divisor. Levels award stars for solving, and more for solving in fewer moves.
Difficulty rises by removing scaffolding rather than by adding complication. Early levels permit only the correct move. Later ones allow wrong moves, so you have to notice one and undo it. Getting better means seeing two or three moves ahead and recognizing that dividing now will force a fraction later, which is the same judgment a written equation demands.
What it exercises
Isolates one term by applying the same operation to both sides
Cancels a term against its opposite to clear a side of the board
Reads symbolic notation with parentheses, fractions and negative signs
Plans a sequence of moves rather than taking the first available one
Collects like terms and factors an expression to simplify a board
Why we rate it High Worksheet score 70 / 100
FitHow much real knowledge or skill does the play itself make you use?80weight 45%
Fit lands at 80, and it is the reason this app earns a place in this catalog at all. The rules of equation-solving are not taught alongside the puzzle; they are the puzzle's only legal moves, so nobody wins by guessing or grinding. The gradual swap from pictures to symbols is the cleverest part, because notation arrives only after the procedure is already automatic.
TransferWill what you practise here work outside the game?62weight 30%
Transfer sits at 62, set by measurement rather than opinion. Studies of this app find high engagement and strong in-game performance, but weak movement to written tests: a player who solves hundreds of boards can still stall on the same equation in a notebook, because the game never actually asks anyone to write one out.
PracticeDoes the game make you use that skill again and again, as it gets harder?60weight 25%
Practice reaches 60. Boards repeat the same operations many times within a chapter, which is genuine drill that does not feel like drill. But the game ends, there is no procedural mode, and most players get through the whole thing in a handful of sittings, which is short for something sold on a subscription.
Where it has been used in teaching
Documented cases of this game being used with learners. Each one links to its source.
StudyCarnegie Mellon University · Secondary school · 2017
Carnegie Mellon researchers randomly assigned 190 seventh and eighth graders to use DragonBox (this app's earlier name) or a research tutoring system for equation-solving over five class periods; DragonBox users solved more problems and enjoyed it more, but scored lower on a post-test.
StudyWorcester Polytechnic Institute · Secondary school · 2023
Researchers studied 253 seventh-graders who used DragonBox 12+ (this app's earlier name) during pandemic remote instruction, finding that higher in-game progress correlated with higher algebra knowledge and end-of-year math achievement, especially for lower-performing students.
StudyUniversity of Oslo, for the Norwegian Directorate for Education and Training (Udir) · Secondary school · 2015
A University of Oslo case study for Norway's ARK&APP programme examined how DragonBox (this app's earlier name) and other learning resources were used for algebra teaching in Norwegian lower-secondary schools, commissioned by the national education directorate.
Research-backedPublished research has studied this game, or the exact mechanic it is built on.
The evidence level is Research-backed, which is rare here and is earned. Long and Aleven (2017), a randomized classroom study of 190 pupils in grades 7 and 8 published in ACM Transactions on Computer-Human Interaction, compared this app against the Lynnette intelligent tutor: students enjoyed the game more and solved far more problems, but gained less on written equation tests. A University of Oslo classroom case study for the Norwegian Directorate for Education and Training reached a similar conclusion, that the notation does not move to notebooks on its own. Chan and colleagues (2023) found a correlation between problems solved and mathematics performance, not a causal effect. All three studied schoolchildren in classrooms, not home play.
Editorial assessment - not a measured scientific effect.
Fit
80/100
Transfer
62/100
Practice
60/100
Why it makes the cut
Pass, narrowly — the isolate-the-box puzzles have genuine solve-it tension and a level progression people play through for its own sake, but the game exists to teach algebra and is sold as a learning app, so it sits at the edge of this catalog.
Research-backed
Research-backed: a randomized classroom trial and a correlational study both measured algebra outcomes with this app directly, finding strong engagement and in-game progress but weak or mixed movement to written equation tests.
App Store ↗FreeIn-app purchasesMobile · Free download; unlock needs a Kahoot! Kids subscription (7-day trial) or a one-time purchase ($19.99 on 2026-09-09) · Checked 2026-09-09
Google Play ↗FreeIn-app purchasesMobile · Free download; unlock needs a Kahoot! Kids subscription (7-day trial) or a one-time purchase ($19.99 on 2026-09-09) · Checked 2026-09-09
Prices are US store listings in USD, last refreshed 2026-09-28; regional prices and sales differ.
This is the app formerly sold as DragonBox Algebra 12+. Kahoot! Algebra by DragonBox (formerly Algebra 5+) covers the same ideas for younger children and is also subscription-only.
Age guidance
Ages 10-17
Topics
STEM
Play styles
Single-player, Puzzle
Tags
Algebra · Subscription · No reading
It rates high because every legal move in the puzzle is a genuine algebraic operation, so players solve hundreds of real equations without knowing it, though measured transfer to handwritten notation is weak, and the game itself is short.
