Here is a worksheet (factorising-quadratics-puzzle) I made that encourages lower-ability pupils to factorise quadratic expressions when a = 1. Each bracket that appears in the answers can be found in the answer bank, which the pupils have to cross off when each one has been used. There are more brackets than they need, which are highlighted on the teacher’s version of the answer bank.
The excellent website Flashy Maths has a nice interactive game involving factorising quadratic expressions. A nice interface, and you can also download this to play offline for a bigger and better version.
Interactive factorising activity – 10 multiple choice questions
Introduction to factorising quadratics – revising expanding brackets and spotting the link between the brackets and the expanded expressions.
Factorising linear expressions.
Factorising basic quadratic expressions – 8 questions on factorising quadratic expressions, where a = 1. An extension problem is included that starts pupils thinking about how to solve quadratic equations that require factorising.
16 questions on factorising quadratic expressions where a > 1
If you find it difficult factorising quadratic expressions where the value of a is greater than 1, here is a really nice little video on YouTube that shows you how to factorise successfully every time using the AC method.