Number Operations

MathsBot: AflCheckup. For quick first 'low stakes quiz'. Select Topic: eg Arithemetic Multiplication, then click on New Question. Play with difficulty to adjust the number of digits/decimals etc.

CorbettMaths: 

Addition: No decimals Decimals

Subtraction: No decimals Decimals

Multiplication by Morley: Scroll down to the Multiplication methods page. He shows the 3 common methods for multiplication.

Chinese Method SFMaths: I favour the 'lattice method' or 'chinese method' or 'napiers bones'. It has less steps (so less to go wrong) and works well for decimals. 

CorbettMaths Multiplication: 

No decimals in these: Questions Answers

Decimals: Questions Answers

CorbettMaths Division:

No decimals Questions Answers

Divide into Decimals Questions

Divide by Decimals Questions

...or kick BIDMAS into touch and use GEMS (Groups, Exponents, Multiplication&Division, Subtract&Division. This is for 2 reasons:

1) This way avoid the misconception that Addition always comes before Subtraction.

2) The G covers things in brackets, under a root sign or as a numerator / denominator.

MathsBot: Pick the topic and adjust the difficulty

Corbett

Questions

DrAustin

Strip: Questions Answers

Grid: Questions Answers

Embedding the use of a number line is key to the understanding of directed numbers. Having a number line printed in all students books as well as a big one on the wall for reference can make life much easier. I like -20 to 20 works nicely for me.

MathsGenie: Questions Answers

The standards units resources are among the best rich tasks available

N8 - Negative Numbers in Context Instructions PPT

N9 - Evaluating Negative number statements Instructions PPT

Corbett Questions

MathsGenie: Questions Answers