Grade 8 Math Games (Ages 13–14)
Play Grade 8 GamesEighth grade is the launch pad for Algebra 1. The big ideas are the laws of exponents and scientific notation, square and cube roots and irrational numbers, slope and slope-intercept form, systems of linear equations solved by graphing and elimination, the idea of a function (exactly one output for each input), transformations and dilations on the coordinate plane, the Pythagorean theorem, volume of cylinders, cones and spheres, and scatter plots with lines of best fit.
This is the year math becomes about relationships rather than answers. A slope is a rate of change, a system is two stories that meet at one point, and a function is a rule you can read from a table, a graph or an equation. Games make that visible: when your child drags a line to change its slope or stacks tiles to cancel a variable, the structure of the math is the thing they are manipulating, not something they are told about.
The games below are grouped by topic and ordered easiest-first; the algebra, functions and geometry lists carry most of the grade 8 load, with number sense and data alongside. Everything runs free in the browser with no ads and no sign-up — and if a topic feels wobbly, the grade 7 page is one click back.
Arithmetic
- Signed Order OpsGrades 7–8Tap operation chips to collapse an expression with negatives, exponents and nested parentheses in any order you like — a wrong order leaves a visibly wrong value, and LOCK IN checks the final number.
- Cube Root CoveGrade 8Drag a cube's side up and down until its volume hits the target — the side you stop on is the cube root; then solve x³ = p and trap ∛n between two whole numbers.
- Magnitude MeterGrade 8Slide a quantity onto a log-scaled meter where every band is ×10 — the band is its power of ten, the spot inside the band its leading digit — then stretch a bracket between two quantities to read how many times bigger one is.
- Power Rules PlantGrade 8Pull the result tower up or below the line until it holds the right number of factor blocks — joined stacks add, cancelled pairs subtract, copied stacks multiply the exponent.
- Repeating Fraction ForgeGrade 8Slide a repeating decimal's digits by ×10, ×100 or ×1000 and hit SUBTRACT — when the tails line up they cancel before your eyes and the fraction falls out.
- Root RangeGrade 8Drag a tiled square until its area hits the target so its side reads as the root, trap √n between two perfect-square tiles on the number line, then zoom the unit into tenths and slide the marker to the tenth whose square lands nearest n.
- Sci Notation ScopeGrade 8Slide the decimal point along the digits — every place it moves ticks the power of ten — to zoom standard numbers into c × 10ⁿ and back, then span the zoom ruler from an atom to the Sun to read how many powers of ten apart they are.
Geometry & Shapes
- Polygon Angle PlazaGrades 7–8Drag diagonals out of one vertex to fan a polygon into 180° triangles and dial the interior sum, then walk the exterior angles round a 360° gauge to find the missing turn.
- Angle Equation ArenaGrades 7–8Dial x (or drag a ray) until angles labelled (2x + 10)° and (3x − 5)° actually obey their vertical, straight-line or right-angle rule — the equation assembles itself under the diagram.
- Coordinate Rule ReactorGrade 8Drag each image vertex to the lattice point a coordinate rule like (x, y) → (−y, x) sends it to — the transformed figure assembles vertex by vertex.
- Dilation DockGrade 8Dial a scale factor and drag the centre of dilation, chain 90° rotations and slides, and solve similar-triangle sides by ratio until the figure docks onto its ghost image.
- Exterior Angle ExpressGrade 8Tear a copy of each remote interior angle and fit it into a triangle's exterior angle — the two stack flush, so exterior = remote + remote is something you see, then dial the one unknown.
- Pythagoras PierGrade 8Tap the leg squares to pour their areas into the hypotenuse square, then dial the side whose square matches — a² + b² = c² as areas you can see, including distance between two grid points.
- Transversal TrailGrade 8Tap every angle equal (or supplementary) to a given one, rotate the transversal until a named angle hits its target while only another angle reads live, and dial an unknown angle from the pair rule.
Coordinates & Algebra
- Graph Story QuestGrade 8Read a short story (a walk, a filling tub, a cooling soup) and sketch its graph by dragging the dot that ends each part up, down or level — steeper means faster, and every sketch that tells the story is accepted.
- Both Sides BalanceGrades 7–8Tap tiles to strip the same x-tiles and unit tiles off both pans of a balance, cancel red −1 tiles with zero pairs, then split what remains so x stands alone — or load a different pan that balances at a given x.
- Crossing LinesGrade 8Drag a ⊕ probe to the one lattice point that satisfies both equations of a system — LOCK IN plugs its x and y into each equation on screen, and parallel or disguised same-line systems must be called as no solution or every point.
- Elimination EngineGrade 8Dial a multiplier on each equation card and stack them so a variable cancels, then solve the leftover equation and back-substitute — elimination and substitution done by hand.
- Function FilterGrade 8Cut the rows that give one input two outputs, drag table points onto a grid to route it linear or nonlinear, and dial a line's rate of change straight off the table.
- Function TranslatorGrade 8Tap columns to plot a function from its table or rule, dial m and b to match a graph, and rebuild the faster of two functions given in different forms — the equation, table and rule stay live-linked to what you build.
- Growth GardenGrade 8Stack each day's leaves on a plant and watch the bar tops plot themselves — equal steps line up straight, doubling curves away, and you lock in which growth is linear.
- Line BuilderGrade 8Slide the ○ on the y-axis to set b and tilt the ◇ on the x = 2 rail to set m — the equation y = mx + b rewrites live as you fit the line to a given equation, plotted points, or a table.
- Slope SlideGrade 8Drag the tip of a slope triangle across a grid — its legs count the rise and the run, and rise ÷ run is the slope you read off a line, aim through a second point, or build from a given m.
- Solution SorterGrade 8Tap a term to subtract it from both sides of a balanced equation until x stands alone or vanishes, then sort the result: one solution, no solution, or every x.
Data & Probability
- Sample ScoutGrades 7–8Draw a random sample from a jar of numbered beads, watch it land on a dot plot, then drag the mean marker to where the data balances, set the ±MAD band, and compare two jars' samples.
- Frequency ForgeGrade 8Drag survey cards into the cell where their two traits meet, dial each group's share as a percentage of the glowing total, then judge from the bars whether the traits are linked.
- Scatter ScoutGrade 8Drag a line of best fit until the residual bars balance, tap the outlier, slide a marker up the line to predict, and dial relative frequencies from a two-way table.
Measurement
- Scale Area ScoutGrades 7–8Stretch a copy by a scale factor k and watch it tile with k × k copies of the original (or stack k × k × k cubes) — lengths scale by k, areas by k², volumes by k³.
- Conversion ChainGrades 7–8Tap unit-factor cards onto a chain and flip them so every unwanted unit appears top and bottom and cancels — what survives is the converted answer, from km/h to m/s.
- Round Volume VaultGrade 8Dial a cylinder's, cone's or sphere's radius or height until the solid holds exactly the target volume — the shape grows under the dial while you work the formula in terms of π.
Common Questions
What math should an 8th grader know?
Grade 8 standards center on exponent laws and scientific notation, square and cube roots and irrational numbers, slope and linear equations in one and two variables, systems of equations, functions (including comparing linear and nonlinear), transformations, dilations and similarity, angle relationships with parallel lines, the Pythagorean theorem and distance, volume of cylinders, cones and spheres, and scatter plots and two-way tables.
How are these games different from a worksheet or quiz?
In a quiz you read a question and tap an answer; here the math is the mechanic. You drag a line to set its slope, stack tiles to cancel variables in a system, or slide a shape through a transformation, so the idea has to be understood to be played. Feedback is immediate, which means mistakes are corrected before they turn into habits.
Will these prepare my child for Algebra 1?
Yes — slope, linear equations, systems, functions and exponent laws are the core of the Algebra 1 on-ramp, and the grade 8 lists cover them in depth. Because the games build the meaning (rate of change, solution as intersection) alongside the procedure, students arrive in Algebra 1 with intuition to attach the new notation to.
Are the games free?
Yes — every game on KidsDoMath is completely free, with no ads, no account and no in-app purchases. They run in the browser on any device, and progress is saved on your device only.
Math Games for Other Grades
Kindergarten · Grade 1 · Grade 2 · Grade 3 · Grade 4 · Grade 5 · Grade 6 · Grade 7