this is an observational tool specifically for math coaches and administrators, to be used for the iPad or iPod touch. research based practices, and it's only $0.99 for a limited time.
This has videos of rich math tasks being used in classrooms, and takes you through the preplanning, launch-explore-summarize of the lesson, and the reflection after the lesson. Student work samples from the actual videos are also available. It's a great resource for coaches and teachers for professional development.