Mr. Smedes is an AP Environmental Science teacher from Grand Rapids, Michigan who has developed (for a price) a whole bunch of very useful review materials. Look at these yourself and see if they are worth the investment for you. In roughly 26 minutes he reviews the key ideas of this first unit on ecosystems.

This is another overall review of Unit 1 if you are looking for an additional quick video review.

This is still another overall review of the first portion of Unit 1 if you are looking for an additional quick video review.

This is still another overall review of the second portion Unit 1 if you are looking for an additional quick video review.