Is Goblins free for teachers?

Yes. Goblins offers a generous free tier that includes 1 live feedback assignment per week, insights on student mastery and replays, and the ability to upload your own content. The Max plan adds unlimited assignments, superadaptive mode, grade exports, standards growth reports, and SSO/LMS integration, with per-student pricing for schools and districts.

How does Goblins work?

Three simple steps: (1) Share an assignment from thousands of standards-aligned topics using a share code. (2) Students speak and draw their thinking naturally, and Goblins responds with Socratic questioning that sounds just like their teacher. (3) Teachers get real-time formative insights showing what students struggle with and suggestions to inform instruction.

Does Goblins prevent cheating?

Yes. Goblins uses a purpose-trained AI model that evaluates cheating signals in real time. It can detect when students are copying answers, using external tools inappropriately, or not genuinely working through problems. Copy-pasting answers is also blocked.

Can I use my own voice with Goblins?

Yes. Teachers can record their voice and take a selfie to create a custom 3D avatar in about 30 seconds. Students then hear help in their own teacher's voice and see a familiar face, making the experience more personal and effective.

What math levels does Goblins cover?

Goblins covers math from Grade 5 through AP Calculus, including thousands of standards-aligned topics. Teachers can also upload their own content for custom assignments at any level.

Is Goblins FERPA compliant?

Yes. Goblins is FERPA and state compliant. Student data privacy and security are a top priority.

Does Goblins support English Language Learners?

Yes. Goblins supports 30+ languages so teachers don't have to translate every worksheet. It is especially helpful for ELL students who need accessible math instruction in their native language.

5.GM.2.1

Determine the volume of rectangular prisms by the number of unit cubes (n) used to construct the shape and by the product of the dimensions of the prism 𝑎 ⋅ 𝑏 ⋅ 𝑐 = 𝑛. Understand rectangular prisms of different dimensions (p, q, and r) can have the same volume if 𝑎 ⋅ 𝑏 ⋅ 𝑐 = 𝑝 ⋅ 𝑞 ⋅ 𝑟 = 𝑛.

Example Problems

A gardening tray is

50 \text{ cm}

long by

15 \text{ cm}

wide. It holds

1875 \text{ cm}^3

of soil.

How deep is the soil in the tray?

A loaf pan is

30 \text{ cm}

long by

10 \text{ cm}

wide. It contains

1500 \text{ cm}^3

of batter.

How deep is the batter in the pan?

A fish tank is

2.3 \text{ m}

long by

0.75 \text{ m}

wide. It contains

1.035 \text{ m}^3

of water.

How deep is the water in the tank?

Khan Academy Resources

Volume of rectangular prisms review Decompose figures to find volume practice Volume formula intuition Volume as area of base times height Volume of rectangular prisms Volume of rectangular prisms with unit cubes Volume word problems Compare volumes with unit cubes Decompose figures to find volume (unit cubes)Measuring volume with unit cubes Volume word problem: water tank Volume of a rectangular prism Volume in unit cubes by decomposing shape Measuring volume as area times length

1-on-1 AI tutoring aligned to 5.GM.2.1. Instant help for students, real-time insights for teachers.

Used in classrooms by 100,000+ students at Baltimore County, Plano ISD, Deer Valley USD, KIPP, and districts nationwide.

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