Hey Mo, you said you want your kids to learn a bit about the Mayan ruins. Well I have a friend in San Ignacio who is a tour guide (Yucatec Mayan/Spanish)and works at Bartons Creek. He loves to teach about his culture while canoeing thu the caves then horseback riding. These are short, simple trips at one place. Also in the area are Cahal Pech and Xunantunich. He would be more than happy to show you these sites. I will be seeing him Monday 4/14 if you are interested email me sweetlilbigheart@yahoo.com.
There is so much to do...you almost dont need to plan in advance! It's a good way to sqeeze lots of adventures in though! Also dont forget to visit Spanish Lookout for ice cream!

Do a search here on whats been written about Tikal.