Activity
Texas Instruments

Texas Instruments: Periodicity of the Periodic Table

For Teachers 9th - 10th
Different properties of the elements of the periodic table will be plotted and from this, a system of organization for the elements will be developed.
Activity
Texas Instruments

Texas Instruments: Getting Started With the Periodic Table App

For Teachers 9th - 10th
In this activity, explore the periodicity of the periodic table with the Periodic Table App.
Activity
Varsity Tutors

Varsity Tutors: Hotmath: Practice Problems: Circular Functions, Periodicity and Symmetry

For Students 9th - 10th
Eighteen problems offer practice working with circular functions, periodicity and symmetry. They are given with each step to the solution cleverly revealed one at a time. You can work each step of the problem then click the "View...
Website
NASA

Nasa: Eclipses

For Students 9th - 10th
The periodicity and recurrance of eclipses is governed by the Saros cycle, a period of approximately 6,585.3 days (18 years 11 days 8 hours). It was known to the Chaldeans as a period when lunar eclipses seem to repeat themselves, but...