It is great that these students are well motivated to make the most of the opportunity for some 'guided' revision, or to just cover some subjects that they feel that they need some help with. For the students are able to have tuition, and those who may not, there are some fantastic websites around which offer video tutorials and a selection of exam style questions to practise. I am including links to a few of them here. All of them are free to use, and provide worthwhile focussed revision. I hope you find them useful.
In the meantime, if you have a son or daughter who will be taking his or her GCSE maths next May/June, and you are thinking of employing a tutor, then please do get in touch as soon as possible, in order to reserve a place for September 2018.