Investigate the effects of the half-lifes of the isotopes of cobalt on the mass of a mystery lump of the element.

Get some practice using big and small numbers in chemistry.

Work out the numerical values for these physical quantities.

See how the motion of the simple pendulum is not-so-simple after all.

Build up the concept of the Taylor series

Work in groups to try to create the best approximations to these physical quantities.

Estimate these curious quantities sufficiently accurately that you can rank them in order of size

An advanced mathematical exploration supporting our series of articles on population dynamics for advanced students.

Work with numbers big and small to estimate and calulate various quantities in biological contexts.

Practise your skills of proportional reasoning with this interactive haemocytometer.

Looking at small values of functions. Motivating the existence of the Taylor expansion.

Analyse these beautiful biological images and attempt to rank them in size order.

10 graphs of experimental data are given. Can you use a spreadsheet to find algebraic graphs which match them closely, and thus discover the formulae most likely to govern the underlying processes?

How many generations would link an evolutionist to a very distant ancestor?

In this twist on the well-known Countdown numbers game, use your knowledge of Powers and Roots to make a target.

Which is larger: (a) 1.000001^{1000000} or 2? (b) 100^{300} or 300! (i.e.factorial 300)

Unmultiply is a game of quick estimation. You need to find two numbers that multiply together to something close to the given target - fast! 10 levels with a high scores table.