The MOOCs, which have lots of explanations of concepts, are best for refreshing your knowledge. The Metric resources have lots of practice questions, and are best for consolidating your skills.
In both cases, you should “dip in” to key parts of the collections, rather than trying to do everything.
Recommendation: start with the MOOCs, and move to Metric if you need extra practice.
To get to the MOOCs, go to edx.org and search “A-level Maths”. Enrol to “audit” the course; that way, you won’t have to pay. The links below should then all work.
general info
Core Revision
Revisit the ideas of algebra, functions and trigonometry.
You’ll need content from Year 12, Course 1; Year 12, Course 2 and Year 13, Course 1. Spend no more than a couple of hours on each module.
Year 12, Course 1
Module 3: Factor Theorem and Algebraic Division
Module 5: Graphical Transformations and Curve Sketching
Year 12, Course 2
Module 2: Exponentials and Logarithms
Year 13, Course 1
Module 1: Algebra and Functions
Module 4: Trigonometry 1
Module 5: Trigonometry 2
To start using METRIC click here. Spend as long as you need on the practice examples. Here’s some content you may find useful.
Topic - Algebra
Unit - Quadratics and Rational Expressions - Lesson(s) - All
Topic - Trigonometry
Unit - All - Lesson(s) - All
Topic - Functions and Graphs
Unit - Functions in General - Lesson(s) - All
Unit - Particular Functions - Lesson(s) - Exponential Functions, Logarithmic Functions
Extended Revision
Revisit the ideas of differentiation and integration.
You’ll need content from Year 12, Course 2 and Year 13, Course 2. Spend no more than a couple of hours on each module.
Year 12, Course 2
Module 1: Differentiation 1
Module 3: Differentiation 2
Module 4: Integration
Year 13, Course 2
Module 5: Differentiation Methods
Module 6: Integration Methods
To start using METRIC click here. Spend as long as you need on the practice examples. Here’s some content you may find useful.
Topic - Differentiation
Unit - All - Lesson(s) - All
Topic - Integration
Unit - Techniques - Lesson(s) - Integration By Inspection, Integration By Parts, Integration By Substitution, Use of Partial Fractions
Unit - Applications - Lesson(s) - All