As you know, I am always looking for ways to include real life math in my classroom. Usually, I manage a project in Geometry but not in my other classes. So I checked out sites for learning the math involved in carpentry.
My school used to offer carpentry but when the teacher retired, they didn't bother replacing him. That is unfortunate. So I needed to check and see where I could find information so I might create a unit for my pre-algebra class and maybe even my algebra class.
One of the first sites I found offers some great carpentry math. This looks at the slope or pitch of roofs. The author relates rise and run to the pitch, to trigonometry and to the Pythagorean theorem. This is so cool because the relationships are shown and it changes the math from being taught in a void to showing them good applications. In addition, the entry includes quite a few formulas associated with roofing and writes many of them so they are related to previous formulas.
The Carpentry Pro-Framer site has some really great information on the math carpenters use. The author talks about easy ways to add or subtract measurements, figuring out how long joists should be, squaring various parts of a building, or locating windows or doors.
It is important to provide some practice problems so students are able to apply the math. I found this online pdf filled with carpentry problems. I find the word problems the most exciting because you are more likely going to encounter a word type problem in the industry rather than just a list of numbers ready to go. The word problems also require students to interpret drawings.
I found a site with a 4.5 min video where a carpenter explains how math is used. The video could easily be used to introduce the topic and covers measurement, fractions, decimals and percents. The way the pdf is structured, problems could easily be integrated into regular assignments so you don't have to take extra time to incorporate it.