🚀 Starlight Station FREE
Skill focus: Add/Sub within 1000
The station drifts into deep space and the codes scramble again — bigger numbers this time. Reboot life support and unmask the saboteur.
🎖️ Play free now → About this case📐 Common Core math practice · Grade 3
Third grade is the multiplication year, and it is the first year the maths can genuinely stall a child. Knowing products of one-digit numbers from memory is the gate everything later depends on — long division, fractions, area — and there is no way through it except repetition. The problem is that repetition is boring, and bored children stop. So in Number Cadets the times tables are the thing standing between your cadet and the culprit: the pirate's plunder will not divide into fair shares, the garden beds will not tile, the library's stacks will not reshelve until the facts are right. Same repetition. Entirely different motivation.
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Skill focus: Add/Sub within 1000
The station drifts into deep space and the codes scramble again — bigger numbers this time. Reboot life support and unmask the saboteur.
🎖️ Play free now → About this caseSkill focus: Multiples, place value & fractions
The villain locked our stolen case files behind a four-layer vault. Beat four fiendish defences — laser grid, bullion balance, gear works and trip-wire alarm — to recover the files and unmask the thief.
Launch activity → About this caseSkill focus: Rounding, fractions & elapsed time
The Grand Library's most treasured book vanished when someone secretly retyped its catalog card. Crack the card catalog, reshelve the scrambled stacks, beat the due-date desk and check the receipts to unmask the book-napper.
Launch activity → About this caseSkill focus: Number patterns, half-inch ruler, bar graphs & quadrilaterals
The Golden Teddy — the carnival's famous grand prize — vanished the night before the big raffle! Crack the ticket booth's number roll, measure the evidence at the sweet stand, rebuild the prize graph and pop only the right balloons to unmask the prize-napper.
Launch activity → About this caseSkill focus: Equal-area fractions, ×, two-step problems
A chest of gold was sworn to be split into fair, equal shares — but one greedy pirate grabbed more than their share and re-buried the treasure! Split the plunder into equal shares, weigh the doubloons, crack the captain's log and fire the cannons to unmask the pirate who broke the code of fair shares.
Launch activity → About this caseSkill focus: Division, area by unit squares, +/− within 1000 & half-inch plots
The prize-winning Golden Sunflower vanished the night before the Bloomtown Flower Show! Bundle the spilled seeds, replant the trampled beds, hop the bee-line trellis and rebuild the sprout charts to unmask the Blooming Bandit.
Launch activity → About this caseAcross the six Grade 3 cases your cadet interprets products and quotients, solves multiplication and division word problems within 100, and works toward knowing every one-digit product from memory. They add and subtract fluently within 1000, round to the nearest 10 and 100, and solve two-step problems across all four operations while judging whether an answer is reasonable. They compare fractions with the same numerator or denominator, partition shapes into equal areas and name them as unit fractions, measure area by counting unit squares, tell time to the minute and solve elapsed-time problems, draw scaled picture and bar graphs, measure to halves and fourths of an inch on line plots, and classify quadrilaterals.
Every question is tagged to one of these 15 standards, and mastery is tracked per standard for each agent. Official Common Core wording:
| 3.G.A.1 | Understand that shapes in different categories (e.g., rhombuses, rectangles, and others) may share attributes (e.g., having four sides), and that the shared attributes can define a larger category (e.g., quadrilaterals). Recognize rhombuses, rectangles, and squares as examples of quadrilaterals, and draw examples of quadrilaterals that do not belong to any of these subcategories. |
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| 3.G.A.2 | Partition shapes into parts with equal areas. Express the area of each part as a unit fraction of the whole. |
| 3.MD.A.1 | Tell and write time to the nearest minute and measure time intervals in minutes. Solve word problems involving addition and subtraction of time intervals in minutes, e.g., by representing the problem on a number line diagram. |
| 3.MD.B.3 | Draw a scaled picture graph and a scaled bar graph to represent a data set with several categories. Solve one- and two-step "how many more" and "how many less" problems using information presented in scaled bar graphs. |
| 3.MD.B.4 | Generate measurement data by measuring lengths using rulers marked with halves and fourths of an inch. Show the data by making a line plot, where the horizontal scale is marked off in appropriate units — whole numbers, halves, or quarters. |
| 3.MD.C.6 | Measure areas by counting unit squares (square cm, square m, square in, square ft, and improvised units). |
| 3.NBT.A.1 | Use place value understanding to round whole numbers to the nearest 10 or 100. |
| 3.NBT.A.2 | Fluently add and subtract within 1000 using strategies and algorithms based on place value, properties of operations, and/or the relationship between addition and subtraction. |
| 3.NF.A.3.d | Compare two fractions with the same numerator or the same denominator by reasoning about their size. Recognize that comparisons are valid only when the two fractions refer to the same whole. Record the results of comparisons with the symbols >, =, or <, and justify the conclusions, e.g., by using a visual fraction model. |
| 3.OA.A.1 | Interpret products of whole numbers, e.g., interpret 5 × 7 as the total number of objects in 5 groups of 7 objects each. |
| 3.OA.A.2 | Interpret whole-number quotients of whole numbers, e.g., interpret 56 ÷ 8 as the number of objects in each share when 56 objects are partitioned equally into 8 shares, or as a number of shares when 56 objects are partitioned into equal shares of 8 objects each. |
| 3.OA.A.3 | Use multiplication and division within 100 to solve word problems in situations involving equal groups, arrays, and measurement quantities, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem. |
| 3.OA.C.7 | Fluently multiply and divide within 100, using strategies such as the relationship between multiplication and division or properties of operations. By the end of Grade 3, know from memory all products of two one-digit numbers. |
| 3.OA.D.8 | Solve two-step word problems using the four operations. Represent these problems using equations with a letter standing for the unknown quantity. Assess the reasonableness of answers using mental computation and estimation strategies including rounding. |
| 3.OA.D.9 | Identify arithmetic patterns (including patterns in the addition table or multiplication table), and explain them using properties of operations. |
That's the case this grade is built for. The multiplication facts are embedded as the mechanism of the mystery rather than presented as a drill, and every case is drawn fresh from the question pools, so they meet the same facts repeatedly in different disguises. Mastery is tracked per standard so you can watch fluency actually arrive.
At Grade 3 level, yes — comparing fractions with a common numerator or denominator, and partitioning shapes into equal areas expressed as unit fractions. Fraction arithmetic proper begins in Grades 4 and 5.
Four clue rounds of five questions, typically 15 to 25 minutes at this grade. Progress saves, so it can be split across sittings.
Yes. Every question is tagged to a specific Grade 3 standard, listed in full on this page with official wording, and mastery is tracked per standard.