Sequence is important in establishing what caused what. Several lessons include documents. It is always good to see authentic first-hand accounts. If you want to know the Israeli position, don't ask the Palestinians, and if you want to know the Palestinian position, don't ask the Israelis. Go to the source.
Numbers are important.
There are several charts. Pay attention to geography. We Americans tend to overlook it. Remember where the major cities are, where the rivers are, where the mountain ranges are. These help us understand how countries relate to each other.