A hole in a piece of paper Animation Play

Democritus's atomic theory Animation Play

Early atomic theories Student activity Play

Equivalent fractions Student activity Play

Harry's lawn Whiteboard exercise Play

John's lawn Whiteboard exercise Play

Parts of a circle's circumference Student activity Play

Pieces of cakes Animation Play

Primary treatment Slideshow Play

Purification of water Student activity Play

Resolution of optical devices Animation Play

Resolution of optical devices Student activity Play

The lawn Student activity Play

The pieces of chocolate Whiteboard exercise Play

The pieces of chocolate on three plates Whiteboard exercise Play

The pieces of chocolate on two plates Whiteboard exercise Play

The ratio of the parts Student activity Play

Three fourths of a circle Animation Play