# The Lesson Study Group

at Mills College

## Teacher Learning Video Clips

 Description of video Link to Video Study curriculum materials In this video clip, team members independently work on a challenging mathematics task and then share their solution strategies. This “mystery strip” task asks teachers to express the length of a mystery strip in meters; they are given only an unruled meter length to do this.  It is a more challenging version of a classroom task designed to reveal unit fractions (fractions with the numerator one) as units to build other numbers: for example, to see that three 1/3’s make 1 and two 1/5’s make 2/5. The team includes two grade 3 teachers, a librarian, and a special education teacher, as well as an outside observer.  We encourage you to try this challenging task before watching the video! Watch video clip Study research and standards In this video clip, the planning team work out what the term ‘unit fraction’ means, how their students understand units and why measurement units might provide a good context for learning fractions compared to prior approaches they have used. Watch video clip Study research and standards After reading Van De Walle’s chapter on measurement and looking at a grade 1 task from Primary Math International (teachers have the reading/task in front of them), they talk about how linear measurement might help their students understand fractions.  They discuss challenges in understanding measurement, including understanding that larger units require fewer iterations to measure a length and counting units rather than tick marks. Review NAEP task/Grade 1 task before watching the clips. Watch video clip part 1   Watch video clip part 2