Jessica and Alex's friendship did not get much screentime this season. I thought they would, since Jess told him that he was the best friend she's ever had in the S3 finale. However, I did like their friendship this season.
Jessica was super annoying and bitchy this season... I felt like Alex was the only one she treated as an equal. She asked him to the dance, did the treasure hunt with him, cried talking about him (and Hannah) during her college interview, looked at him before the walkout for support even though she had both Clay and Justin by her side and was happy for him at Prom. Alex seemed annoyed with her at first, but he texted her during the lockdown (I was pissed that she didn't answer) and confessed to protect her at the end. I also liked what Alex told her in episode 8, "It always has been you and me."
I hated how none of them are facing repercussions for their actions, but I kind of liked that Jess and Alex both ended up at Berkeley.