Khan Academy

Multiple rates word problem | Ratios, proportions, units, and rates | Pre-Algebra | (KA)

Unit measurement word problem: running laps (US customary) | Algebra I (KA)

Perimeter and unit conversion | Ratios, proportions, units, and rates | Pre-Algebra | (KA)

Unit measurement word problem: volume (US customary) | Pre-Algebra | (KA)

Proportion validity example | Ratios, proportions, units, and rates | Pre-Algebra | (KA)

Unit measurement word problem: weight (US customary) | Pre-Algebra | (KA)

Ratio word problem: boys to girls | Pre-Algebra | (KA)

Ratio word problem: centimeters to kilometers | Pre-Algebra | (KA)

Ratios as fractions in simplest form | Pre-Algebra | (KA)

Simplifying rates and ratios | Ratios, proportions, units, and rates | Pre-Algebra | (KA)

Solving ratio problems with graph | Pre-Algebra | (KA)

Solving ratio problems with tables example 1 | Pre-Algebra | (KA)

Solving ratio problems with tables example 2 | Pre-Algebra | (KA)

Solving unit price problem | Ratios, proportions, units, and rates | Pre-Algebra | (KA)

Solving unit rates problem | Ratios, proportions, units, and rates | Pre-Algebra | (KA)

Speed translation | Ratios, proportions, units, and rates | Pre-Algebra | (KA)

U.S. customary and metric units | Ratios, proportions, units, and rates | Pre-Algebra | (KA)

Unit conversion within the metric system | Pre-Algebra | (KA)

Area of a circle (K-A)

Area of circles review (K-A)

Circumference review (K-A) pdf

Finding circumference of a circle when given the area (K-A)

Labeling parts of a circle (K-A)

Partial circle area and arc length (K-A)

Radius, diameter, & circumference (K-A)