🚀 Starlight Station FREE
Skill focus: Order of ops, multiply & divide
The crook scrambled the station's master equations and locked the reactor vault. Out-think them, run the numbers, and seal the case.
🎖️ Play free now → About this case📐 Common Core math practice · Grade 5
Fifth grade is the bridge to middle school, and it is quietly about notation. Parentheses and brackets start changing what an expression means. Exponents appear, at least for powers of ten. A fraction stops being a piece of pie and becomes an instruction to divide. Decimals extend to thousandths and have to be multiplied and divided, not merely compared. None of this is harder arithmetic than fourth grade — it is arithmetic with more rules about how to read it, which is exactly the kind of thing that gets skimmed and then quietly breaks algebra two years later. The cases at this grade are built to punish skimming: the vault's expression lock only opens for the correct order of operations.
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Skill focus: Order of ops, multiply & divide
The crook scrambled the station's master equations and locked the reactor vault. Out-think them, run the numbers, and seal the case.
🎖️ Play free now → About this caseSkill focus: Expressions, decimals & division
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: Dewey decimals & conversions
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: Powers of ten, expressions, division & shape hierarchy
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: Fractions as division, decimals & division
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: Powers of place value, fraction problems, rounding decimals & line 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 caseSkill focus: Volume by layers & formula, expression codes & fraction problems
The night before the big Toy Fair, someone jammed the great toy factory's machines and hid its masterpiece — the Wind-Up Wonder! Run the packing line, wind the racers on the test track, re-teach the sorting scanner and fix the blueprints to unmask the Toy Trickster.
Launch activity → About this caseAcross the seven Grade 5 cases your cadet uses parentheses, brackets and braces in numerical expressions, evaluates them correctly, and interprets what an expression means without having to evaluate it; explains patterns of zeros and decimal-point placement when multiplying or dividing by powers of ten, using whole-number exponents. They read, write, compare and round decimals to thousandths, and add, subtract, multiply and divide decimals to hundredths. They multiply multi-digit whole numbers with the standard algorithm and divide four-digit dividends by two-digit divisors. They measure volume by counting unit cubes and relate it to length × width × height, add and subtract fractions with unlike denominators in word problems, interpret a fraction as division, solve real-world problems multiplying fractions and mixed numbers, convert units within a system in multi-step problems, plot fractional measurement data, and classify two-dimensional figures in a hierarchy.
Every question is tagged to one of these 17 standards, and mastery is tracked per standard for each agent. Official Common Core wording:
| 5.G.B.4 | Classify two-dimensional figures in a hierarchy based on properties. |
|---|---|
| 5.MD.A.1 | Convert among different-sized standard measurement units within a given measurement system (e.g., convert 5 cm to 0.05 m), and use these conversions in solving multi-step, real world problems. |
| 5.MD.B.2 | Make a line plot to display a data set of measurements in fractions of a unit (1/2, 1/4, 1/8). Use operations on fractions for this grade to solve problems involving information presented in line plots. |
| 5.MD.C.4 | Measure volumes by counting unit cubes, using cubic cm, cubic in, cubic ft, and improvised units. |
| 5.MD.C.5 | Relate volume to the operations of multiplication and addition and solve real world and mathematical problems involving volume. |
| 5.NBT.A.1 | Recognize that in a multi-digit number, a digit in one place represents 10 times as much as it represents in the place to its right and 1/10 of what it represents in the place to its left. |
| 5.NBT.A.2 | Explain patterns in the number of zeros of the product when multiplying a number by powers of 10, and explain patterns in the placement of the decimal point when a decimal is multiplied or divided by a power of 10. Use whole-number exponents to denote powers of 10. |
| 5.NBT.A.3 | Read, write, and compare decimals to thousandths. |
| 5.NBT.A.4 | Use place value understanding to round decimals to any place. |
| 5.NBT.B.5 | Fluently multiply multi-digit whole numbers using the standard algorithm. |
| 5.NBT.B.6 | Find whole-number quotients of whole numbers with up to four-digit dividends and two-digit divisors, using strategies based on place value, the properties of operations, and/or the relationship between multiplication and division. Illustrate and explain the calculation by using equations, rectangular arrays, and/or area models. |
| 5.NBT.B.7 | Add, subtract, multiply, and divide decimals to hundredths, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used. |
| 5.NF.A.2 | Solve word problems involving addition and subtraction of fractions referring to the same whole, including cases of unlike denominators, e.g., by using visual fraction models or equations to represent the problem. Use benchmark fractions and number sense of fractions to estimate mentally and assess the reasonableness of answers. *For example, recognize an incorrect result $\frac{2}{5} + \frac{1}{2} = \frac{3}{7}$, by observing that $\frac{3}{7} < \frac{1}{2}$.* |
| 5.NF.B.3 | Interpret a fraction as division of the numerator by the denominator (a/b = a ÷ b). Solve word problems involving division of whole numbers leading to answers in the form of fractions or mixed numbers, e.g., by using visual fraction models or equations to represent the problem. |
| 5.NF.B.6 | Solve real world problems involving multiplication of fractions and mixed numbers, e.g., by using visual fraction models or equations to represent the problem. |
| 5.OA.A.1 | Use parentheses, brackets, or braces in numerical expressions, and evaluate expressions with these symbols. |
| 5.OA.A.2 | Write simple expressions that record calculations with numbers, and interpret numerical expressions without evaluating them. *For example, express the calculation "add 8 and 7, then multiply by 2" as $2 \times (8 + 7)$. Recognize that $3 \times (18932 + 921)$ is three times as large as 18932 + 921, without having to calculate the indicated sum or product.* |
It targets the Grade 5 standards middle school assumes: order of operations, powers of ten, decimal arithmetic, fractions as division, and the standard algorithms. Those are precisely the things that, left shaky, cause trouble in Grade 6 algebra.
The stories are pitched to be enjoyable rather than cute, and the maths at this grade is genuinely demanding — a Grade 5 case is not a Grade 2 case with bigger numbers. That said, this is the top of our range, and some cadets will be ready to move on.
Not currently. Number Cadets is K–5. We'd rather cover six grades properly than eight thinly.
Yes. Every question is tagged to a specific Grade 5 standard, listed in full on this page with official wording, and mastery is tracked per standard.