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-MD taught?

This standard is part of the S-MD curriculum in Alaska Mathematics Standards.

S-MD: Using Probability to Make Decisions

Using Probability to Make Decisions

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Using Probability to Make Decisions applies probability concepts to evaluate strategies and analyze outcomes in real-world decisions. Random variables and their probability distributions are defined and graphed, and expected value is calculated and interpreted. Probability models inform decisions in contexts such as product testing, medical diagnostics, and game strategy.

S-MD.1(+) Define a random variable for a quantity of interest by assigning a numerical value to each event in a sample space; graph the corresponding probability distribution using the same graphical displays as for data distributions.S-MD.2(+) Calculate the expected value of a random variable; interpret it as the mean of the probability distribution.S-MD.3(+) Develop a probability distribution for a random variable defined for a sample space in which theoretical probabilities can be calculated; find the expected value. For example, find the theoretical probability distribution for the number of correct answers obtained by guessing on all five questions of a multiple-choice test where each question has four choices, and find the expected grade under various grading schemes.S-MD.4(+) Develop a probability distribution for a random variable defined for a sample space in which probabilities are assigned empirically; find the expected value. For example, find a current data distribution on the number of TV sets per household in the United States, and calculate the expected number of sets per household. How many TV sets would you expect to find in 100 randomly selected households?S-MD.5(+) Weigh the possible outcomes of a decision by assigning probabilities to payoff values and finding expected values.S-MD.6(+) Use probabilities to make fair decisions (e.g., drawing by lots, using a random number generator).S-MD.7(+) Analyze decisions and strategies using probability concepts (e.g., product testing, medical testing, pulling a hockey goalie at the end of a game).

Example Problems

A different product's reviews have the following distribution for star ratings T.

T	1	2	3	4	5
P(T)	0.08	0.12	0.28	0.30	0.22

Find the indicated probability.

P(T \geq 4) =

A fair coin is flipped 5 times. Let

X

be the number of heads. What is the expected value of

X

?

In a game you roll a fair six-sided die. You receive (3 times the number showing) dollars minus 5 dollars. What is the expected payout?

An animal‑shelter manager tracks daily adoptions.
Let

A

= the number of animals adopted in one day.

A = # adopted	0	1	2	3	4
Probability	0.15	0.35	0.30	0.15	0.05

Find the mean of

A

.

A photocopier has a

12\%

chance of breaking this month, which would cost

\$900

to repair; otherwise, there is no repair cost. What is the expected repair cost for the month?

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