Thinking Summary · 1
MasteredEquation Logic: .
[Discovery] How many thousandths are in 0.678? (Type a whole number.)
1
Active StepWelcome to "Probe Decimal Compare", a 5th Grade Decimals mission at the Explorer (core) level, staged in our space exploration scenario. The mission opens with a hands-on prompt: "How many thousandths are in 0.678? (Type a whole number.)" You'll reason about the numbers 0, 678, 687 across 3 guided steps.
Behind the space exploration story, this lesson is really about decimals aligned to CCSS 5.NBT.A.3. Read, write, and compare decimals to thousandths using base-ten numerals, number names, and expanded form. The key strategy this mission asks you to internalise: 678 vs 687 — bigger number wins.
A general pattern to watch for in 5th Grade decimals — illustrated with example numbers below, which may differ from this lesson's: Believing trailing zeros change a decimal's value. 0.4 = 0.40 = 0.400. Trailing zeros after the decimal point are place-value padding, not new value. If you get stuck on "Probe Decimal Compare", 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 5 · Decimaladvanced
Mission Progress
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Thinking Summary · 1
MasteredEquation Logic: .
[Discovery] How many thousandths are in 0.678? (Type a whole number.)
1
Active Step5th Grade Decimals explorer-2 representative practice page for students who need a crawlable, worked entry point into the topic without exposing every near-duplicate long-tail mission.
This explorer · core practice mission uses a number sentence to move from the story to a precise decimals idea. Work through the prompts in order: notice the structure first, name the quantities, then check whether the final answer fits the original situation.
In 5th Grade Decimals, students need to connect the story, the model, and the symbolic answer. The core move here is: 678 vs 687 — bigger number wins. A useful check is to ask whether the answer avoids this pitfall: Thinking 0.65 > 0.7 because 65 > 7. Add trailing zeros to align: 0.65 vs 0.70. Now 70 > 65 in the same unit.