Add a two sentence story to your puzzles. Many children don’t need them, but the half of your class with too much testosterone will appreciate a Klingon attack on Earth or a shark attack in the local swimming pool 😉
My perception is that girls are neither more or less motivated when these testosterone-rich, destructive stories are used to introduce a puzzle… but I do try to mitigate the aggressive language by including other perspectives. Empathy engages both sexes. Instead of just describing a puzzle in terms of testosterone-rich language – like “Earth Attack” add something about “Trying to Save Earth.” Instead of just a shark in the swimming pool – add the role of the lifeguard.
I do not add stories to all my puzzles. I have had fantastic success with abstract puzzle designs that look beautiful. However, to achieve high engagement levels puzzles must be buttressed by either beauty or a story.