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.

8.SP.2

Explain why straight lines are widely used to model relationships between two quantitative variables. For scatter plots that suggest a linear association, informally fit a straight line, and informally assess the model fit by judging the closeness of the data points to the line.

Example Problems

A fishery biologist recorded the length of trout, in centimeters, and their weight, in grams.
After plotting her results, the biologist noticed that the relationship between the two variables was fairly linear, so she used the data to calculate the following least squares regression equation for predicting weight, in grams, from length, in centimeters:

\hat{y} = -150 + 6x

What is the residual for a trout that is

32 \text{ cm}

long and weighs

55 \text{ grams}

A mobile carrier recorded each customer's monthly data usage, in GB, and their monthly bill, in dollars.

After plotting their results, the analysts noticed that the relationship between the two variables was fairly linear, so they used the data to calculate the following least squares regression equation for predicting the monthly bill, in dollars, from data usage, in GB:

\hat{y} = 20 + 8x

What is the residual for a customer who used

7 \text{ GB}

and was billed

\$84

A fitness trainer recorded the number of steps a client took in a day and the calories burned, in calories.

After plotting her results, the trainer noticed that the relationship between the two variables was fairly linear, so she used the data to calculate the following least squares regression equation for predicting calories burned from steps taken:

\hat{y} = 200 + \frac{1}{25}x

What is the residual for a day with 8000 steps and 560 calories burned?

Khan Academy Resources

Eyeballing the line of best fit Estimating the line of best fit exercise

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