Answers on a postcard

A much better day today. We played a bit of a prank on year 5, to get them to read instructions. We sent an assignment that told them to read all the instructions before starting the task. The final instruction said to ignore all the previous instructions and take a photo of themselves in their garden and send it to us. Needless to say I had multiple messages telling me the task made no sense etc. I just replied to read all the instructions very carefully and do exactly what they were asked to do. Finally I started receiving photos, meaning they had actually done the right thing.
Which brings me to my blip, this creature was on the sunroom wall just before bedtime. Charlie nearly ran a mile when he saw it! I just picked it up and put it the the garden. Any ideas what it might be?