Welcome to "Donut Variable Test", a 6th Grade Expressions mission at the Challenger (stretch) level, staged in our bakery scenario. The mission opens with a hands-on prompt: "Use algebra tiles to build the expression 17x + 28." You'll reason about the numbers 17, 28, 8 across 3 guided steps.
Behind the bakery story, this lesson is really about expressions aligned to CCSS 6.EE.A.2. Write, read, and evaluate expressions in which letters stand for numbers. The key strategy this mission asks you to internalise: Answer: 164.
A general pattern to watch for in 6th Grade expressions — illustrated with example numbers below, which may differ from this lesson's: Reading "3x" as "3 plus x" instead of "3 times x". A coefficient next to a variable means MULTIPLY. 3x = 3 × x. If you get stuck on "Donut Variable Test", the adaptive Socratic hints below escalate from a gentle nudge to a worked-out strategy — the same way a one-on-one tutor would coach you through it.
Grade 6 · Expressions
Mission Progress
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Thinking Summary · 1
Mastered[object Object]
[Discovery] Use algebra tiles to build the expression 17x + 28.
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Active StepBuild 17x + 28 using x-tiles and 1-tiles.
Everything you need to know about the Socratic experience.
Use algebra tiles to build the expression 17x + 28. Hint: Each x-tile counts as one x. Each 1-tile is a unit. You need 17 x-tiles and 28 1-tiles.
In the expression 17x + 28, what is the constant? If you get stuck, the adaptive hint is: Answer: 28.
Challenger missions push beyond CCSS expectations with edge cases that surface deeper misconceptions. Within 6th Grade Expressions, expect numbers in the corresponding range.
Translating "3 less than n" as "3 - n" instead of "n - 3". "Less than" REVERSES the order. "3 less than 10" = 10 - 3 = 7.
Variables (Variables are the substance of expressions.). Open /grade-6/variables to start that topic's missions.
Inquiry-based learning starts with a question, not a formula — students explore, hypothesize, and verify before being told the rule. In Inquiry AI, every mission opens with a "Discovery" step (manipulate the model), then "Abstraction" (write the equation), then "Reflect" (apply to a new case). The procedure is never given upfront; learners derive it from their own observations.
Yes. Every mission, handbook page, and topic hub is mapped to a specific CCSS code (visible in the page header). The curriculum follows the CCSS coherence map: Grade 1 number sense → Grade 3 multiplicative thinking → Grade 6 ratio reasoning, with each grade building strictly on the prior year's foundations.
