So my moms astro van doesn't want to turn on. I turn the ignition and nothing, the lights wont turn on either. I tried with jumper cables and nothing. I then tried jumper cables directly to the battery cables and cranks a little but not enough to turn on van. Im pretty sure its not the alternator because it should turn on without assistance from it, correct?
I took starter and battery to autozone to have them tested and they were fine. Is there something else to look at or what's going on.

my moms van kinda had the same problem but it wouldnt start in the rain and it turned out bein the distributor cap. hope u r able to fix ur problem;)

Did you check your battery cables to see if they are corroded? It sounds to me like you're not getting a good connection at the battery itself. Start by removing the cables and pulling the battery bolts out of the cable ends. If the cable ends are crusty, take a small cup of Coca Cola and let the cable ends soak in it for a few minutes. You may have to scrape inside with a screwdriver to get all the crud out. Make sure that the contact material is clean on both sides. Give this a try, and re-post here to let me know what you found. Good Luck and God Bless,
Revredneck