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When kids learned how to count, they basically just learn numbers as some kind of continuum that continues and continues. As they go to a higher level of schooling, children might not understand how it goes in groups of tens and hundreds and thousands.

For children to understand place value, otherwise known as the decimal system, they have to learn first how to do simple additions and subtractions with small numbers. Later, you can explain that if you have lots and lots of objects, the efficient way to count them would be in groups, not individually. Here's how you can introduce decimals to kids:

1. You can use white, red, and blue inexpensive poker chips. The white are ones, the blue are tens, and the red are hundreds. Dump a bunch of them on a table and show how it is easier to count them in groups of ten. Then you can count them in groups of tens. Introduce the words 20, 30, 40, etc.

2. got It is better to use same size objects so children can picture the color chip in their mind as representing a group rather than belonging to a group. That is because in writing numbers, the digit '5' represents fifty when written on a structured place.

3. Then write this down. The crucial point in teaching a child about decimals is that a certain column represents a certain size group. The digit in the columns tells the child how poker chips are organized. For example if white is ones, blue is tens, and red is hundreds then two red chips with one blue and one white would be 211. You can use this method to further illustrate the way we write numbers in columns which indicates the group they belong.

Now, do not use the word "represent" when teaching decimals. Instead, talk about trading, exchanging and making: "You can trade 10 white ones for 1 blue." Then you may start asking complex questions: "If you have 15 white ones, what can you trade$%: I have two blue ones, how many whites can I get$%: How can you make the number 54 with the chips, using the LEAST possible amount$%:"

Continue until children can easily make numbers with the chips. This way they will understand the concept that one chip in a particular order represents a group. This is a prelude to understanding how a certain column represents a group.