Tag Archives: trig

358. A spatter of trig

The fabulous Mrs D (@mrsdenyer ) shared this forensics video, by crime scene analyst Matthew Steiner, on Twitter. At eight minutes in the presenter looks at blood spatter analysis. The use of basic trigonometry in a practical situation is a gift of a video for a starter in lesson.


My class were absolutely silent throughout and wanted to watch the whole video, however they may have just been trying to avoid work. I shared the video link with them via our digital classroom platform. We are now using blood spatter for 3D trigonometry examples rather then mobile phone masts. Gory, but effective!

13. Trigonometry Snapdragon

I wanted to boost my students’  level of understanding of trigonometry without switching off their enthusiasm. We’d investigated the tan ratio practically and introduced sin and cos.

Now the tricky bit – how to make picking and rearranging trig rules interesting!

Introducing the Trigonometry snapdragon:


Pinch together the two things in the question eg opposite and hypotenuse.


Look inside the snapdragon at the pinched portions. Follow the instructions eg Sin rule: know hyp, find opp or know opp, find hyp


Unfold the appropriate section for your problem.


You now have the correct rule, rearranged for your problem.


Student Feedback
‘That is amazing’ and ‘Can I make one in the exam?’.

Download a digital version here: Trigonometry snapdragon v2

Also visit the updated snapdragon page for a blank template: Snapdragon fun