Math Lab

Short challenges

A minute of mathematics. These are the small habits — estimate first, check the sign, read the structure — that separate confident students from anxious ones.

Students engaged in online mathematics learning

Try one

Challenges

Reveal the hint only when you are stuck, and the explanation only when you have committed to an answer.

Spot the mistakeFoundationHigh School60s

A student solves x² = 5x and concludes x = 5. What went wrong?

x^2 = 5x \;\Rightarrow\; x = 5

Topic: Quadratic equations

Estimate firstFoundationMiddle School30s

Without a calculator, is √72 closer to 8 or to 9?

Topic: Number sense

Which is correct?IntermediateHigh School45s

y = −(x − 3)² + 4 opens which way, and where is its vertex?

y = -(x-3)^2 + 4

AOpens up, vertex (3, 4)
BOpens down, vertex (3, 4)
COpens down, vertex (−3, 4)

Topic: Quadratic graphs

Mental mathFoundationMiddle School20s

What is 18% of 250?

Topic: Percentages