https://uk.ixl.com/math/word-problems – This website is brilliant! It shows you the different skills that you need in each year group and gives you some example questions.
http://nrich.maths.org/frontpage – Try some abstract maths problems.
http://www.bbc.co.uk/bitesize/ks2/maths/ – BBC Bitesize Mathematics Resources
http://www.educationquizzes.com/ks2/maths/ – Quick Maths Quizzes