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.

AFDA.DA.2.b

Investigate, describe, and determine best sampling techniques, such as simple random sampling, stratified sampling, and cluster sampling.

Example Problems

The parks department will repaint 5 of 50 trail markers. They number the markers

01-50

and use the random digit table printed below to choose a simple random sample.

Which markers are in the sample?

76054, 41328, 37961, 20584, 43310

A research lab prepared 33 culture plates and will test a simple random sample of 5. The plates are numbered 01-33 and the random digit table printed below is used.

Which plates are in the sample?
54140, 32930, 21965, 40788, 15302

A teacher has 10 group leaders and needs a simple random sample of 3 to present first. He numbers them

0-9

and uses the random digit table printed below.

Which leaders are in the sample?

72291, 73905, 14462

Khan Academy Resources

Simulation and randomness: Random digit tables Sampling methods Simple random samples Sampling method considerations Systematic random sampling Random number list to run experiment Random numbers for experimental probability Techniques for random sampling and avoiding bias Techniques for generating a simple random sample

1-on-1 AI tutoring aligned to AFDA.DA.2.b. 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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