1.   There are numerous websites where you can find lesson plans. I'm only suggesting few URL's as a sampler.

    http://www.psrc-online.org/resource/teacher.html

    http://askeric.org/cgi-bin/lessons.cgi/Science/Physics

    http://www.iit.edu/~smile/physinde.html

    http://www.colorado.edu/physics/2000/index.pl

    http://www.mindspring.com/~physics1/

    http://www.glenbrook.k12.il.us/gbssci/phys/Class/Bboard.html

    http://school.discovery.com/lessonplans/physci.html

2.   The quadratic formula is something you use when it is not so easy to spot the factors. In fact it is quick and easier to solve a quadratic than to look for the factors sometimes.

In general if the quadratic equation is written of the form

    ax² + bx + c = 0

Then the factors or values of 'x' which can satisfy this equation are given by

x = {-b ± [b² - 4a.c]}/2a

The term in curly brackets {-b ± [b² - 4a.c]} is called the discriminant. Its value indicates the nature of the roots.

If the discriminant is > 0, then the two roots are real and distinct.

If the discriminant is = 0, then the two roots are equal.

If the discriminant is < 0, then there are not real roots.

Suppose you write an some equation say

    3x² - 8x - 11 = 0

Instead of looking for factors you just plug the values of a, b and c in the formula and simplify. In this problem

a = 3, b = -8, and c = -11

Substituting in the formula

x = {8 ± [(-8)² - 4(3)(-11)]}/2(3) = {8 ± 14}/6

giving you the roots for x as

x = 8 - 14/6 = -1 or

x = 8 + 14/6 = 3.7

Check:

In general, if ß and ð are the two roots, then

    ß + ð = -b/a

    ß x ð = c/a

In our case, let's check the answers.

    3.7 - 1 = 2.7 = 8/3, correct, and

    (3.7) x (-1) = -3.7 = -11/3, correct too.