Multiplication Explorer

Interactive multiplication explorer: build a deep understanding of multiplication through visual arrays and pattern discovery.

Associative Property Lab

Interactive manipulative demonstrating the associative property of addition and multiplication.

Commutative Property Lab

Interactive manipulative demonstrating the commutative property of addition and multiplication.

Place Value Odometer

Interactive base-10 odometer for young learners. Spin the digit wheels and watch carrying cascade left through each place value column.

Fraction Lab

Interactive fraction explorer. Adjust the numerator and denominator to see the fraction as a bar model, number line, decimal, percentage, and equivalent fractions.

Operations Explorer

Interactive explorer for addition, subtraction, multiplication, and division. Pick two numbers and an operation to see the equation with its vocabulary, counter and array models, number line jumps, fact families, and properties like commutativity.

Making Math Fun

A Grades 4-7 lesson on why math can be fun: the difference between passive scrolling and active play, the top online math game sites, an interactive roll-and-solve dice widget, and nine unplugged card, dice, and board games to play at home.

Distributive Property Lab

Interactive manipulative demonstrating the distributive property of multiplication over addition.

Plug-It-In: Substituting Values for Variables

Interactive algebra lab for grades 5-8. Substitute values into geometric formulas for area and volume across 12 shapes, with a step-by-step substitution machine, formula browser, and practice challenge.

Beating the Odds

A Grades 4-7 interactive probability lesson. Explore the likelihood scale, calculate favorable-over-total, play coin and dice experiments to see the Law of Large Numbers, scratch a simulated lottery ticket, and master a 5-question quiz.

Weights & Measures

Explore Imperial and metric measurement systems through interactive conversion tools. Covers length, weight, volume, speed, and temperature for grades 5-8.

Scale & Magnitude

Explore scale and magnitude from atoms to galaxies. Interactive labs cover the cosmic zoom, powers of ten, scale factors, and order-of-magnitude estimation for grades 4-7.

The Infinite & the Infinitesimal

A wonder-driven lab exploring infinity and the infinitesimal for grades 4-7. Features the Endless Counter, Hilbert's Hotel, Zeno's Walk, the Planck length ladder, and an 8-question quiz.

The Going Rate

A Charlotte-edition interactive lab on rates for grades 4-7. Explore 30 rates across 6 domains, from stock markets to the drifting Moon. Features a live ticker, rate builder, spectrum slider, and 10-question quiz.

Mirror Mirror

An advanced symmetry lab for grades 6-8. Explore reflections on the number line, absolute value as distance, additive inverses (opposites), multiplicative inverses (reciprocals), and even vs odd function symmetry, with a reflect-a-point tool, a distance meter, an opposite finder, a reciprocal flip tool, a symmetry grapher, and a challenge quiz.

Functional

A complete interactive reference for the NC Scientific Calculator: trig and inverse trig, mean/stdev/stdevp, nPr/nCr/factorial, exponents and roots, e^x, abs, round, ln, log, and the constants e and pi, each with a live try-it demo and a 6-question quiz.