Decimal Cards

Purpose:

The purpose of this activity is to help your child understand decimal place value.

What you need:

A deck of cards with the face cards and jokers removed (aces count as 1s and 10s count as 0s).

What to do:

Choose a target decimal number (eg 4.825).

Deal each player 6 cards (two more cards than the number of digits in the target number).

Each player has to construct a number as close as possible to the target number. For example if a player is dealt 3, 4, 4, 5, 7, 9 the closest number they can make is 4.795.

The player whose number is closest wins a point.

The winning player chooses the number for the next round.

You can play either that the first player to get 5 points wins, or whoever wins the most out of 10.

What to expect your child to do:

• Use place value to decide which cards to use and in which order.
• Be able to tell you how many ones, tenths, hundredths etc in the number.
• Understand that the cards in the higher ‘places’ make more difference to the overall size of the number than those in the smaller ‘places’.

Variations:

• Change the number of decimal places in the target number.
• Require that the number be the closest possible number less than the target number.
• Require that the number be the closest possible number more than the target number.
• Include the jokers and allow them to be used as a wild card (any digit).

He Kupu Māori:

He Whakawhitinga Kōrero:

• Māku e tuhi tētahi tau ā-ira. He tau matiwhā, e toru ngā mati ā-ira. (I’ll write down a 4 digit number, it’s got 3 decimal digits.)
• Ko te [rima ira rua whitu ono] te tau ā-ira. E tohu ana te mati [whitu] i te aha? (The number is [5.276]. What does the [7] digit represent?)
• E tohu ana te [whitu] i te [whitu haurau]. E noho ana te [whitu] ki te uara tū o ngā [haurau]. (The [7] represents [7 hundredths]. The [7] is sitting in the [hundredths] place value.)
• Riwhiriwhia ngā kāri. Tohaina kia ono ngā kāri ki ia kaitākaro. (Shuffle the cards. Deal 6 cards to each player.)
• Whakamahia ō kāri hei hanga i tētahi tau ā-ira e tino pātata ana ki te tau i tuhia e au. (Use your cards to make a decimal number that is very close to the number I wrote down.)
• E hia ngā mati ā-ira kei roto te tau i hangaia e koe? (How many decimal digits are in the number you made?)
• Kei a wai te tau e tino pātata ana ki te tau nāku nei i tuhi? (Who has got the number that is closest to the number which I wrote down?)
• He pātata ake tāku i tāu nā te mea ko te whitu te mati haurau i tāku, ā, ko te toru te mati haurau i tāu. (Mine is closer than yours because 7 is the hundredths digit in mine and 3 is the hundredths digit in yours.)

Download a file of this activity:

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