If money is a bit tight, you might want to try to sit down with her yourself. Maths is, in my view, a bit like abs. 15 mins every day is way more successful than an hour every week.
The first thing I would do is talk to the teacher and ask her the planned maths topics for the next 4 weeks. You must of course tackle all the bits and pieces she doesn't mastered but it is important to work on what they are actually doing in class, so if they are doing angles, you are not doing fractions.
You could do 15 min of the current topic in class, which will help her get confidence and another 15 min of the basics.
Some will shout that this is way too much, it is actually not. There are excellent websites Khan academy is one (free) , mathsonline is another used here in the classroom (www.mathsonline.com.au/plans ) they do free trials.
You need a good resource book. I have use this series with my children www.cambridge.edu.au/education/titles/ICE-EM-Mathematics-Year-5-Third-Edition-print-and-interactive-textbook-powered-by-Cambridge-HOTmaths/#.XZ91xC17HUo , ups might want to look for something similar in UK.
I would favour a classic book, paper and pencil over any online activity and only use websites for the video lessons in case you want an alternative way of teaching.
Mastering the times tables is a must, and this comes with endless repetition. On the tiles next to the bathtub, I wrote them all with lipstick. For example, on one tile I would write 4x7 , and DC would have to call the answer. In the car, while cooking, endless timetables.
You can do it yourself. Borrow books from your library. GO to a very bog bookshop and go into their educational resources section and sit down there going through the books they have and find the one you find more useful. Organise a learning space at home, a clean desk with the two chairs and sit with her.
Best of luck