I've always taught angles in parallel lines as Fs, Cs and Zs, but I recently discovered that pupils prefer to think of Fs, Us and Ns, which work in exactly the same way but may be easier to remember because they spell the word FUN. (image from greatmathsteachingideas.com) Of course there's still the challenge of remembering the more formal descriptions that they will need to use in their GCSE exam (for example they are required to use the term 'corresponding angle' in their answers, instead of F-angle). I suggest that they think of 'FC' (football club - as in Tottenham Hotspur FC) for F angles = corresponding angles. I also suggest they could remember that Z angles = alternate angles by thinking of the first and last letters of the alphabet. But this doesn't work if I change Z to N! I'll have to think of something else (or even better, get them to come up with something). Resources There are loads of good resources for teaching this topic. Here are a few examples: I love the 'Spot the Angle' activity from mathspad.co.uk. This website also has a great interactive Parallel Lines Tool. Teachitmaths.co.uk has a great angle card sort activity and useful revision cards. Mark Horley has made a Basic Angle Properties activity. Missbrookesmaths.com has a nice angles in parallel lines tick or trash activity. There are a number of angle chases here - thanks to @MathedUp. Greatmathsteachingideas.com has a number of lovely worksheets, activities and applets including Angles in Parallel Lines Colouring Fun and First Letter Prompts which gets pupils thinking about the language of their angle fact answers. This comprehensive booklet 'Introducing Angles' by Gareth Evans is helpful. There are loads more resources for this topic in my shape resources library. More Angle Facts On a related note, here's some tips for teaching more basic angle facts: Marie Darwin's blog suggests that we remember the sizes of acute, obtuse and reflex angles by noting that the sizes from smallest to largest are in alphabetical order. She also points out that the A in the word Acute makes an angle less than 90 degrees (see picture). For remembering that complementary angles add up to 90 degrees, you could think of a compliment as being the right thing to do. mathsisfun.com has a couple more ideas - I like their suggestion that the C of the word complementary stands for 'corner' (ie a right angle) and the S in supplementary stands for 'straight' (ie 180 degrees on a straight line). Interestingly, the word complementary comes from Latin completum (meaning completed) because the right angle is thought of as a complete angle.