What tools do foresters use in the field?  What can trees tell us about their environmental history?  How can foresters use Math?  Students will get to core a tree and read the story it tells about that tree’s environmental history.  Using increment borers to get core samples and looking at cross sections of trees, students can learn how the rings of the tree can tell us stories relating to the local environment over the last x number of years.  They could also learn about the differences in cell structure and tree growth through the season and how this results in creating rings in the trees.  Depending on math levels, we could use angles, Pythagorean Theorem, and/or sine/cosine laws to estimate the height of a tree. 
With some groups, we might measure the circumference of trees and use estimation and calculation to figure out the diameter at the base and again higher up at the level of our ropes course platforms.  From there, rate of growth (height and/or diameter) based on estimated age of the tree could be determined... the possibilities are endless!  Not all of these would be done with one class as the background knowledge needed for some of them is high school level mathematics whereas other activities only require 3rd grade level math skills.