Any child can progress if they do an extra 90 minutes of maths at home in addition to the 5 hours they do at school.
But despite doing 5 hours at school, they dont always cover all aspects of a maths strand, there are disruptions, children who dont understand, they dont get it themselves, they only cover a topic in one lesson, it isnt explained clearly. There are many reasons.
Then the next time they cover the topic, its moved on a step, and they didnt get it the first time, so struggle at the next stage,and this builds up.
The teacher doesnt always notice because there are 30+ kids to cope with.
So then their confidence goes, they are no longer good at maths, they then hate maths and switch off.
Doing online maths isnt a chore, and I personally would prefer that that they are learnin something if on the computer rather than playing mindless games that have no educational value.
Doing 10-15 minutes a day is nothing, all they need to do is two maths games, or revise two maths games. They probably spend more than that in front of a computer.
The OP asked if anyone had used Whizz. We do and it works. It has its faults like all computer games, but it has helped fill in the gaps where my DC were actually struggling. I havent extended them beyond their year group, so they are covering their real year group of maths and consolidating everything that they have been taught, and are now clear on areas they struggled with.
Parents spend hours on computers. Look at the time we all spend on Mumsnet. Is this doin us any good?