My favorite part about this applet is that it has delayed feedback. It is important that the teacher provide students with opportunities to evaluate and critique their own or one another’s conjectures, which is often ignored in applets without delayed feedback. I am definitely going to utilize this when I get to teach transformations and I’m sure my students will enjoy it. ]]>

All you need for polar coordinates is a compass and a ruler to fix the radius, and blank sheet of paper.

The practical computer approach hides the difficulty in Cartesian coordinates by numerical evaluation of power series expansions of the circular functions (sin and cos). For graphics the pixel map is generally Cartesian and polar coordinates are mapped to it.

Your question brings out a nice collection of math, computation, and technology. Thanks to Dan for providing the forum.

]]>1) Teachers and administrators explain the policy at the start of the year. Students can possess cell phones but they MUST be powered OFF in classrooms, including study halls. Cell phones are allowed during lunch/recess in the cafeteria or outside. Use in the hallways between classes is discouraged but has no consequence, which is fine.

2) If Sarah’s cell phone is ON in my class or being viewed or used I simply email her name to our AP after class. Without confrontation I will simply let Sarah know that she was in violation. She already knows that the limit for violations is 3.

3) When the AP receives 3 notifications that Sarah’s phone was ON (this includes all her classes/teachers) in classrooms, he will randomly appear in some other class or even in the cafeteria and calmly confiscate it – as per the policy. Student never refuse this request. They get their phone back at the end of the day.

4) On the second violation, now 6 instances of Sarah’s phone not being powered OFF in the classroom, her phone is randomly taken and returned.

5) On the third infraction, now 9 violations, the phone is taken again, however a parent or guardian must now come in to reclaim it.

Students are reminded that if they forgot to power OFF their phone before entering class, they can raise their hand and request a moment to do so.

The success of this policy has worked wonders to eliminate cell phone use in my building. Teachers absolutely love it because both distractions (phone use and the ensuing confrontation) have eliminated after a brief period of strict enforcement at the start of the year. As long as teachers remain vigilant, cell phone use in the classroom remains a non-issue!

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