To ask for ideas for my DS’ animal welfare club?

[MadamMedusasPawnshop]

Hi everyone. Sorry to ask here, but all your brains will be better than mine...please help me if you have any ideas because I’m stumped!

DS recently joined an animal welfare club at school. He’s 14. They discuss issues like battery farming, living conditions of circus animals abroad, the dog meat trade, the importance of spaying, etc. They’re keen to recruit new members but don’t seem to have any idea how to do it.

Are leaflets or posters the best idea? They need to raise some funds for the printing - any ideas what sort of fundraising might appeal to teenage boys? They’re not allowed to sell fizzy drinks or sweets at school. My son asked me last night and I had no idea what to suggest... I have no imagination How do you think they could encourage other like-minded boys to join?

Is this a boys only school?

Sell stamped dog tags and cat tags, you can get the flat disks and metal stampers at craft stores.
Super fast and easy to personalize, and can be done at low cost
Advertising on line is basically free, maybe a tweet blitz?

Would they be allowed to wash teachers' cars at lunchtime, or parents' cars at pick up?
At DD's school, they sold Krispy Kreme donuts which KK provide at a discounted price. Not sure if that falls into the same category as sweets though.
Or a cake sale, if allowed?

@Aquamarine1029

Yes, boys only!