This is a game for any number of players  though 3 or 4
is best  who sit in a circle around a flat playing surface.
Each player has a set of number cards (initially, the
numbers 0  10) and secretly chooses 4 cards, which he or she lays face down
in front of them IN ASCENDING ORDER FROM LEFT TO RIGHT. The remaining cards
play no part in the game and are concealed from sight. (Players are allowed
to look at their own cards to remind themselves what they have chosen but
they may not look at other players' cards.)
Taking turns, players now try to guess the numbers on
other players' hidden cards.
So, for example, the first player must point to a
specific card of any of the other players and state their guess, "I think
that's a 5."
The player whose card is being guessed must turn it
faceup if the guess is correct  otherwise play passes to the next player
to make a guess.
When all of a player's cards have been guessed (and are
faceup in front of the player), that player takes no further part in the
game. (As games last only a few minutes each, they will not have long to
wait.)
The winner is the last player still to have hidden cards
facedown in front of them.
Players will probably want to play a number of games 
and may wish to keep a tally of how many times each player has won.
STRATEGY
The game can be played by very young players  who will
no doubt guess numbers at random.
Slightly older children will realise that the numbers on
faceup cards give a clue to the hidden numbers on facedown cards (as cards
are arranged in numerical order left to right.) They will also try to
remember previous guesses.
Older players still will devise more complex strategies
regarding which cards they choose to guess, etc.
VARIATION
Instead of using number cards from 0  10, players could
use cards numbered 0  100, or only cards that are multiples of 3, etc.
