I Need Help with...
First off, your best bet for any subject from arithmetic to calculus is Khan Academy. Just go to their website, create an account, click on the subject you need help with and voila! You will find videos and notes, plenty of examples, and even practice problems to quiz yourself on.
Other Great Resources below if you need help with ...
Graphing
more to come
Trigonometry
Degrees vs. Radians - lengthy but an excellent and easy to read explanation of how we measure angles
more to come
Algebra
more to come
Geometry
more to come
Precalculus
more to come
Calculators & Online Calculators
Nothing is better than what we use in class, so it is recommended that you purchase a TI-84 calculator for personal and home use. However, you will learn in class how to do everything without the use of the calculator, but your final exam is 100% calculator active so it would be tremendously helpful to own one.
https://www.amazon.com/Texas-Instruments-TI-84-Graphing-Calculator/dp/B0001EMM0G
https://itunes.apple.com/us/app/free-graphing-calculator/id378009553?mt=8
Finding Your Way Around Your Graphing Calculator
Everything you need to know about your graphing calculator.