This field-tested hidden image worksheet gives good solid practice in French phonetics, focusing on 8 common vowel and nasal sounds. It uses basic words with which high beginner students should be familiar.
The image (fall leaves blowing in the air) is difficult enough to see before it is coloured that students will remain curious about what it is fairly far into the process, and is beautiful once completed. To help with intuitive thinking, the colour code is designed to match with the sound to be coloured where possible (rouge for the sound "oo", etc.).