The lesson plan on the Exploration of Medicinal Plants (http://ankn.uaf.edu/Curriculum/Units/medplants.html) found on the Alaska Native Knowledge Network site integrates Indigenous knowledge with Science curriculum outcomes, giving students experience learning first hand about where and how medicinal plants are used.
At the International School I worked at in Singapore, I had the opportunity to be involved in our Open Minds program which was based on experiential learning outside of the classroom. Holistic connections were made with our natural environment and with examining issues through different perspectives. For example, when I taught Grade 2, one of the sites we visited was the Eco Garden at the Singapore Science Centre. (http://www.science.edu.sg/exhibitions/Pages/ecogarden.aspx) where we examined the different uses of medicinal plants.
The next step for this program would be to add in connections to Indigenous cultures, for example working with elders who have knowledge of the local plants and their uses. It is also very important to ensure students learn about Indigenous communities connections to the the land and environmental sustainability.