Law of Sines and Cosines and Desmos Geometry!

I do Standards Based Grading and I don’t grade homework. All of my students grades are based on assessments. Recently I have been giving my students graded assignments. I try to design them so that they take the students through different types of problems and have a reflection. I let them work with each other, check their answers with Desmos, and come to see me for help if needed. I’ve only done two this year, but many of my students really liked them. They said that the stress was lower than on assessments because they could ask me questions. They also liked working with each other and being able to check their work. After the graded assignment, I usually give another assessment, and I have noticed a large improvement in grades, especially from students who usually score lower on assessments. Students tell me that the graded assignments really helped them learn and understand the topic better.

This chapter I gave them a graded assignment on vectors and the law of sines and cosines. They have already learned the ambiguous case  with the law of sines, and some students seemed to be relying on memory, but I could tell they really didn’t understand what was going on. So I decided to have them finish constructing a couple of triangles, and to take them through the ambiguous case with law of cosines.

Today I gave them an activity builder where they had to do an ASS triangle with the law of cosines, and helped them learn how to use the Desmos Geometry tool. I want them to be able to check their answers on their graded assignment with Desmos Geometry. I haven’t used Desmos Geometry with students yet, but it was really fun today! Plus,  I love that they learned a new tool.

If you use this, I would LOVE feedback!  🙂

Law of Cosines AB using Desmos Geometry– I loved how some kids actually made the ONE triangle instead of the two separate ones.

Triangles Graded Assignment, docx

Triangles Graded Assignment pdf

Trigonometric Identity Activities

Trigonometric identities – I adore them.  They are like little challenging puzzles.  But high school students don’t always share my ardor.  I wanted them to understand what an identity actually was so I started the unit with Sam’s amazing Pythagorean Identities lesson.

The lesson was a little tough for my Algebra 2 class, so I helped them through the last two pages.  The next day, I had them white board some basic trig identity problems.  I usually just give them one side to simplify for starters.  This helps with the whole, “OMG – it’s adding fractions – but with trig!!” scare.  On the third day I put them in pairs to work on Shireen’s (Math Teacher Mambo)  Trig Identity Match Up activity.

This activity was fantastic because all of the identities were the steps in the simplifying process!  So even after they had matched them all up I had them put the cards in the correct order.  What a great activity!

I didn’t see this activity about having students create their own identities (from Sam as well), but I wish I would have!  I will definitely incorporate this next year!