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.

What grade level is M3.S.ID.A.2 taught?

This standard is part of the M3 curriculum in Tennessee Academic Standards for Mathematics.

Are there practice problems for M3.S.ID.A.2?

Yes, there are 3 practice problems available for M3.S.ID.A.2 with worked examples.

What learning resources are available for M3.S.ID.A.2?

There are 2 Khan Academy resources available for M3.S.ID.A.2, including 1 videos, 1 exercises.

M3.S.ID.A.2: Use statistics appropriate to the shape of the data distribution to compare center (mean, median, and/or mode) and spread (range, interquartile range, and standard deviation) of two or more different data sets.

Use statistics appropriate to the shape of the data distribution to compare center (mean, median, and/or mode) and spread (range, interquartile range, and standard deviation) of two or more different data sets.

Example Problems

Here is a table giving the number of neighborhood adults by bike usage and helmet use:

Helmet use	Rides bike	Does not ride bike
Always	45	10
Not always	15	30

Find the marginal distribution of bike usage in counts.
Rides bike =

Here is a table giving the number of neighborhood adults by bike usage and helmet use:

Helmet use	Rides bike	Does not ride bike
Always	45	10
Not always	15	30

Find the marginal distribution of bike usage in counts.
Does not ride bike =

A running club recorded a sample of 4 training runs. Here are the distances (in miles):

2, 3, 4, 5

The mean of these distances is

\bar{x} = 3.5 \text{ miles}

.

What is the standard deviation,

s_x

?
Round your answer to two decimal places.

Khan Academy Resources

Comparing distributions Mean and standard deviation versus median and IQR

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