Master core mathematical concepts through our interactive Socratic curriculum.
Search Intent Match
This hub is for students who need free multidigitmult practice that shows the reasoning, not just the answer. It groups 30 browser-based missions around multiplying larger numbers by decomposing place value, aligned with 4.NBT.B.5.
The companion guide explains it as: Multiply a whole number of up to four digits by a one-digit number, and multiply two two-digit numbers, using strategies based on place value.
Practice Goals
Common Mistakes
Use Cases
Use before the standard algorithm so each row has meaning.
Ask the student to name the partial products before adding them.
Complete one mission, then say what changed, what stayed the same, and why the final answer makes sense.
Indexable Practice
Everything you need to know about the Socratic experience.
There are 30 missions in this topic — 10 Seedling (entry-level), 10 Explorer (core), and 10 Challenger (stretch). Each mission has 3 Socratic steps with adaptive hints.
This topic is aligned with CCSS 4.NBT.B.5. Open the topic guide for the standard's full text and a step-by-step breakdown of the cognitive sub-skills.
Start with Seedling missions to anchor the visual model, then move to Explorer for the core abstraction, and tackle Challenger only when Explorer is flawless. Difficulty badges on each card show this progression.
Grade 4 is when arithmetic becomes *strategic*. We teach the area model first so the standard algorithm feels like a shortcut, not a magic trick.
We use the rectangle test: every rectangle a child can build with N tiles is a factor pair. Primes are the numbers that only fit in 1×N strips.
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.
C-P-A is the Singapore Math sequence proven to deepen number sense: first manipulate physical objects (Concrete), then draw pictures of them (Pictorial), and only then write equations (Abstract). Inquiry AI structures every mission as exactly these three steps — a manipulative, a picture/grid model, and finally the equation. Skipping straight to symbols is the #1 cause of math anxiety; the platform refuses to do it.
