In the US the Experimental Aircraft Association (EAA) has a fabulous program called Young Eagles:
https://www.eaa.org/eaa/youth/free-ye-flights
Free rides for kids 8-17. I try to take part in one or two rallies per year and I am always the only helicopter there.
If you do decide to support the Young Eagles program drop me a PM, there are special procedures for helicopters (for example they waive the shutdown between loads rule) and I can point you to them, or call the coordinator at EAA and ask for them. You do have to join the EAA to participate.