The question here is whether you classify yoga as a fitness exercise or as education (or instruction). In WA you are required to collect sales tax on exercise classes, but not on instructional classes. Yoga is so much more than exercise, but can we argue that all yoga classes involve the mind and education? I have been to some yoga classes both at gyms and yoga studios that were no different than aerobics classes, with no mention of the breath, the mind, or philosophy.

I live in Seattle and I'm following this issue on my blog, Chai & Yoga (http://chaiandyoga.com/). There's a public meeting on November 19 to discuss the yoga tax issue. Stay tuned!

It already is in my province of Ontario (Canada). I never think about it. It just "is".

I live in Seattle and my yoga studio charges sales tax. I wouldn't have thought it to be exempt from sales tax.

We have the same law here in CT. Everyone was upset when it came out 5+ years ago. "How can you force us to pay for taxes on health improvement." was the main cry from the public. But if we want to go to yoga class we have to pay little extra for it. This is a part of life.
The studio and gym I go to had to include sales tax starting on a certain date. They were not force to pay back taxes.

This is an interesting issue in light of the challenges to Yoga as a religion in public schools. If it is a religion, they can't tax it. If its not a religion, then there should be no limits on it in public schools.