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 S-ID taught?

This standard is part of the S-ID curriculum in New Jersey Student Learning Standards - Mathematics.

S-ID: Interpreting Categorical and Quantitative Data

Interpreting Categorical and Quantitative Data

Print

Interpreting Categorical and Quantitative Data covers the full pipeline of descriptive statistics. Students represent single-variable data with dot plots, histograms, and box plots; compare center and spread; then move to two-variable data through scatter plots, regression, and two-way frequency tables. A third cluster focuses on interpreting slope, intercept, and correlation coefficients of linear models.

S-ID.ASummarize, represent, and interpret data on a single count or measurement variable S-ID.BSummarize, represent, and interpret data on two categorical and quantitative variables S-ID.CInterpret linear models

Example Problems

What is the critical value

z^{*}

for constructing a 90% confidence interval?

An ornithologist wants to look at the relationship between the breadth of peregrine falcon eggs and the mass of the falcon chicks that hatch from them. The data show a linear pattern with the summary statistics shown below:

	mean	standard deviation
x = egg breadth (mm)	$\bar{x} = 41$	$s_x = 2.3$
y = chick's mass (g)	$\bar{y} = 33.6$	$s_y = 4.6$
		$r = 0.95$

Find the equation of the least-squares regression line for predicting the chick's mass from the breadth of the egg, in the form

\hat{y} = a + bx

.
Round your entries to the nearest hundredth.

A tutoring center director wants to look at the relationship between hours of tutoring and final grades. The data show a linear pattern with the summary statistics shown below:

	mean	standard deviation
$x$ = hours of tutoring	$\overline{x} = 8.5$	$s_x = 2$
$y$ = final grade (points)	$\overline{y} = 81$	$s_y = 10$
		$r = 0.89$

Find the equation of the least-squares regression line for predicting the final grade (points) from the hours of tutoring, in the form

\hat{y} = a + bx

.
Round your entries to the nearest hundredth.

Identify any outliers from the following table:

Data Value
84
7
9
8

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}

?

1-on-1 AI tutoring aligned to S-ID. 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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