# 88. Factor (Nasty) Game

Today, it’s a classic maths game which has been passed around for at least 12 years, if not longer. It develops basic number skills such as multiplication, division, factors, primes, squares and place value.

Equipment
A whiteboard (or wall or floor)
Ten digit cards (0-9): you could also just write the digits, but cards are more fun/tactile.
Blu-tak
Mini-whiteboards (or paper)
Calculators are optional

Before you start
You need between 2 and 5 teams. Five gives you more tension/excitement.

Each team needs a whiteboard.
Indicate on the board where each team puts their cards. They need tens and units columns.

Blu tak the number cards to the board.

Basic game
Each team takes it in turn to pick a card and place it in one of their columns. This is repeated so that every team has a two digit number. If you have five teams, there will be no leftover digits.

Winners
The winning team is the one whose number had the most factors. It is up to the teams to prove this by giving all the calculations of factors. Other teams may challenge their accuracy. You can also discuss why some numbers have an odd number of factors (eg square numbers) or exactly two factors (prime numbers).

Time to get Nasty
I said this game was called Factor Nasty … and it is.

There is only one change to the game rules: you can pick a digit and put it in any team’s answer box. They can use their number skills to really stitch each other up.

Imagine Team A puts a 0 in Team C’s tens column. Then Team B puts a 3 in Team C’s units column. Team C can’t do anything to improve their number, but they can make life tricky for Team A and B. Meanwhile, Teams D and E ignore them and create really good answers.

Have fun trying this as a starter or plenary!