
From the KS3 National Curriculum we see the above on algebraic notation, see also pages 56-66 of the Teaching mathematics at key stage 3 guidance. The guidance covers the entire KS3 curriculum and includes common difficulties and misconceptions, examples for use in lessons, and suggested questioning and other strategies for teachers to use.

The following slideshow includes several resources you can use with students for practice in writing algebraic notation.
Included you can see Jonathan Hall’s Worded Expressions, as always with MathsBot resources we have lots of choices – for example, hide either the sentences or expressions. With the ability to generate new expressions we have an endless supply; also from Jonathan Hall, see his Forming Expressions, these resources are ideal for self-study as well as for use in class.
From Don Steward, we have translating English to algebra, expressions, see also translating English to algebra, relationships. Also included here is an activity, A1 from the Standards Unit on Interpreting algebraic expressions. This includes 4 card sets to match, ideal for looking at multiple representations, students match algebraic expressions, explanations in words, tables of numbers and areas of shapes. One of the goals of the activity is to help learners to translate between words, symbols, tables, and area representations of algebraic shapes. The Standards Unit resources can all be accessed without a login from the very clear to navigate University of Nottingham site linked to in the Standards Unit post.
One of Chris McGrane’s Starting Points MathsCurriculum Booklets – Algebra 1 from Phase 3 features some great activities for writing algebraic statements, featured on the slides you can see a Smile activity, and Jo Morgan’s lovely Introduction to Writing Algebraically – this is such a good idea, as Jo says in the resource description if they know how to do it with numbers, then they just do the same thing with the algebra.
Further excellent resources on this skill are available on Maths4Everyone.
On Transum, Writing Expressions is an exercise with a difference, listen to the audio then type in the expression.
From Corbett Maths
Algebra: expressions – forming Video 16 Practice Questions Textbook Exercise
16. Algebra: expressions – forming Practice Questions answers Textbook answers
From Andy Lutwyche – Algebraic Expressions Spiders
Here’s an interesting query type on WolframAlpha – simple word problems. See more examples of Word Problems (and All Examples by Topic).

From my post on Bar Modelling see The Mathenæum from Ken Wessen which includes Modelling Word Problems.
