

We suggest that you
introduce this game by showing the group how to play it. Deal out four
cards, then a fifth, and ask the group if they can make an equation that
uses some or all of the four cards to equal the number on the fifth. Give people a few
minutes to work on their own, writing down possibilities that they come
up with. Then ask what people’s equations are. Write the equations
down for everyone to see. Try to show examples
of equations using two numbers (worth 4 points), equations using three
numbers (worth 9 points), and equations using all four numbers (worth
a whopping 16 points). Addition, subtraction,
multiplication, and division are all acceptable operations to include
in equations. Depending on how advanced your players are, you may want
to allow other operations, such as square roots, exponentials, factorials,
and so on. An equation can yield
different answers, depending on the order in which you do the operations.
(See Where’s the Math?) That’s why
it’s important for players to use parentheses when writing equations.
When doing the mathematical operations in an equation, one always does
the operations that are in parentheses first. People should use parentheses
to make it clear which operations to do first. Once players understand
the rules, they can play independently in groups of two to five. Alternatively,
you can have an entire class or large group play together. The leader
deals out the cards and keeps track of time. Once time is up, players
calculate their own scores. Ask who has the highest score, then check
her or his equations together. Or have players swap papers and check each
other’s equations. You might want to remind everyone that a player
gets 7 points for finding someone else’s mistake! Are people having
trouble finding an equation that works? It may help to focus on finding
combinations that lead to 1’s or zeros. Suppose you get stuck trying to use 3, 4, 7, and 7 in an equation that equals 4. You can get rid of unwanted numbers by creating a zero, like this:
because zero can never
be on the bottom of a fraction (in the denominator). Suppose you’re trying to use 3, 4, 7, and 7 in an equation that equals 7. You could get rid of unwanted numbers by turning them into a "1," like this:
Go to Playing Fantastic Four with Cards 



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