Perhaps I am just your average geek but I do like to use stats. In KY the avg volunteer hour is worth $14.08. That is kind of an eye opener. I also like to talk about how comfortable it makes kids to see another mom, dad, or grandparent at school. Sometimes teachers are intimidating to students. I was very intimadated by teachers and most grown ups when I was a little girl. What few times I did see a mom it made me feel better. Personal experiences go a long way. If you put different spins on it, someone will say; "Hey, I never thought of that." Also most people do not know that the volunteer hours logged in help in getting grants.
I've done so much research and reports on this for my classes I use alot of things from there.
www.nea.org
and
www.educationworld.com
has some interesting research on this matter. For example:
Students with involved parents are more likely to:
Go to college
Have better social skills
Earn higher grades
Enroll in higher level classes
The list goes on and on. The positive effects are endless.
Laurib's games sound cute. After a quick intro about the importance you could use that game. I did something like that in my Psych class and it was pretty neat.