Human80:
For us the issue was finding support in maths. We opted for Mathsfactor - it marks the work for the child & you can check results. It keeps you posted (either by e-mail or you can just log in to your parent dashboard) and see how your child is doing, explanation of what is coming next, preview of lessons, etc....
Info here: www.themathsfactor.com/
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READING:
To be honest just encouraging regular reading is a huge help.
Try to make time to listen to them read a few nights a week and if you can try and give them a break and read to them now and then. We have a nice mix of DDs reading to us (whilst one or the other is having their bath) and us reading to DDs (usually at weekends) from books we enjoyed as children.
Writing is trickier but solutions are there:
Thank you cards (for presents/ nice days out/ etc...)
Post cards on trips
letters to competitions rather than e-mails
we also encourage fan letters - to favourite authors or tv shows/ personalities.
Both DDs keep diaries as well. I think it is a way to 'vent' about each other, me & DH - but also to work through issues at school they feel less comfortable talking to us about (there's a lot of low-level bullying at our school).
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Great Free Websites:
Woodland Junior School Homework Help: resources.woodlands-junior.kent.sch.uk/ - highly recommend Maths Zone: resources.woodlands-junior.kent.sch.uk/maths/index.html
St Ambrose Spelling pages: www.saintambrosebarlow.wigan.sch.uk/spellingpage.htm
BBC Bitesize KS1 (Y1/ Y2 - prep for Y2 KS1 SATs): www.bbc.co.uk/bitesize/ks1/
BBC Bitesize KS2 (Y3 - Y6 - better for Y5 onwards - but difficulty can be set): www.bbc.co.uk/bitesize/ks2/
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My personal feeling is that if you encourage reading of good quality children's fiction & keep maths ticking over - you'll be going a long way to helping your child long term.
Our school has had some huge issues with regular delivery of homework, especially in maths. So we've found doing 1 hour - 1 1/2 hours of extra maths a week was a huge help - but DD1 scored NC L1 (below expected progress) at KS1 SATs so we were doing a lot of remedial work in Year 3 - by Year 4 it was such a part of our 'routine' - doing a bit of maths whilst I was making dinner/ cleaning just became the norm.
HTH