For lots of interactive graphing models, this site allows you to create graphs and copy them to a document or web page. I would like to create a Math Trail, but I don't have time to take my students out into my community. If time is an issue, you don't really need to send your students into the neighborhood. You can create a Classroom Math Trail or even a School Campus Math Trail. Since math exists all around you, there is no limit to the math you can find right where you are.
Students can also work on a math trail as a homework assignment.
Have them do it as a home project over a weekend. It's a good opportunity to have them team up with their classmates. See what they come back with. I will give these problems to my students to work in class. This will help us with Missouri history while integrating mathematics.