When teaching traditional strategies, you will need a few months to help young children learn it thoroughly.  Use directed instruction, start with the basics and do not move on to another concept if the first one is not completely understood.  Terms such as trading, grouping and exchanging must be given priority by doing appropriate exercises.

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Explain to them how they are going to learn something 'cool' today in the same way that their parents and teachers have learned it when they were in school.  This will get them motivated to know what grown-up's know.

Start with Models only 

At first, let them only record their answers but try to avoid written work as far as possible.  Give each of them "Tens Frame working mats" such as these:

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They should start by writing a number at the top and also a second number too as you can see in the example that I give below (top portion).  They can also use counters which will help them to make groups.  It is important for them to learn that they should work from right to left, thus starting in the ones column.  They can try this exercise by themselves to see if they can solve it.  Give them enough time and interact with them along the way - this will make them more productive and they will feel in-charge of the problem given.

Motivate them to keep a written record

It might be easier for them to keep records with simple charts such as these:

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Resources:

Resource 1

Resource 2