I have received many questions about NAPLAN testing. The following information may be of support.

Develop Test Literacy
Please note that I am NOT in favour of practising test after test. Children, especially Year 3 children, will need to become ‘test literate’. Children need to understand how to:

• enter answers, 
• keep track of time, 
• use their ‘number sense’, ‘spatial/measurement sense’ or ‘data sense’ to reduce the choice of answer from four to three.

ACARA provides sample NAPLAN tests and answers
These would be ideal for help children understand how to ‘take a NAPLAN test’. For example:
Sample 1 | Sample 2

The answer guide is published at the NAPLAN website.

I worked in one school where the children rotated from one task to the next every ten to twenty minutes. When they were confronted with a test that lasted 45 – 50 minutes they soon fatigued because they were not used to concentrating for such a length of time.
 

Offer a Balanced Program
If students are given a mathematical diet consisting of mostly number and basic number facts you could be doing your students a disservice. The following extract from the letter sent from ACARA to teachers in 2016 makes the following comment:
 

In the NAPLAN numeracy test, the proportion of items in the test from each strand will match the proportion of the strand content in the Australian Curriculum: Mathematics. As a result, there will be slightly fewer ‘space items’ (for example, features of 2D shapes and 3D objects) and more number, statistics and probability items than in past tests. The space items are now known as ‘geometry items’.
– Source
 

Acara, 2016

Improve Children’s Mathematical Literacies
In order to answer a written question children will need to be able to:

• read it
• comprehend it
• translate it into the mathematics required
• encode it into the form required

Anne Newman(1977), a teacher in NSW developed a system now called the “Newman Analysis” designed to help teacher determine where the breakdown in reading and interpreting a mathematics question might be occurring. See here

If you search for Newman Analysis you will find various presentations and notes on the use of the Newman system.

Improve Mathematical Vocabulary
Many students struggle to read NAPLAN numeracy tests so it makes sense to improve the mathematical vocabulary of your students. There are several sources of mathematical vocabulary including the glossary found in the Australian Mathematics Curriculum.

I like the booklet produced under the national Numeracy Strategy in the United Kingdom as word are grouped under year levels and topics. See here

Graphics
Around 70% of NAPLAN questions include a graphic. Some graphics are important, others not so. 
See “Graphics in Mathematics” here on my site.

Symbols 
Not many symbols are used in Year 3 NAPLAN tests, but the use of symbols increases as the tests get harder. Students need to be taught not only to recognise symbols but also their meaning. 
See “Symbols in Mathematics” 

Note these support documents are based purely on my opinion. They were designed as a catalyst to discuss aspects of testing in general and NAPLAN test specifically. I have noted the vocabulary used and I have left a column for teachers to look at the test and note how graphics and symbols are employed throughout the test