Loose Threads:

How much pizza do they manage to eat?

If the pizza there is so bad, why do they keep going back?

Why is the poem taped to the painting instead of just a part of it?

Why did Daria and Jane simply deface the painting instead of restore it, which would have proved much more embarrassing to Ms. Li?

Notables:

Daria is an eavesdropper. When Ms. Defoe talks to Jane, Daria hangs around just outside the door to listen in.

There was a mouse hole on the side of the house that Daria and Jane stop in front of to talk.

Jane calls Daria a real Joan of Arc, and Daria responds with "and I think I just ordered a steak(stake)." Joan of Arc was a French woman who believed herself to be the chosen of God, and who help rallied French resistance against English invaders, and ended up being burned at the stake by the church.

Charles is actually a good painter.

Jane can be rebellious just for the sake of rebellion, but Daria has principles behind her rebellion.

Ms. Defoe thinks it's a good piece of art even though she has to have it explained to her.

Daria is very Libertarian in her outlook. "I don't really care what people do to themselves."

Lawndale High's mascot is a lion.

First appearance of Jane's mother, Amanda. However...
What does Mrs. Lane look like?
It seems that Jane got her taste for arts from her mother.

Mr. O'Neill goes out of his way to avoid speaking with the fathers of his students, then totally freaks out when he talks to Jake.

Helen seems to have planned responses to Daria and Quinn's school related problems. Even so, she isn't used to the Principal calling.
She also seems to have her assistant do Quinn's homework whenever the teachers complain about her not doing it.

The Morgendorffers eat dinner around 7 PM.

When Jake makes a rational and coherent comment that supports Daria (against Helen), Helen gets really immature and dumps pasta on his head.

Mr. O'Neill's comment about a spoon full of sugar helping the medicine go down is, as Daria points out, a Mary Poppins quote.
Oddly enough, there is a thing called Syrup of Ipecac that was used to induce vomiting...

Jodie knows Daria and Jane well enough to be suspicious of their presence.

Jane mentions "we had to destroy the work in order to save it," a take off on a US soldier's statement "We had to destroy the village in order to save it."

Mistakes:

The house with the mouse hole that Daria and Jane talk in front of changes color in different shots.

The number and position of the pizza plates in front of Daria changes in different angles.

Mr. O'Neill's phone only has nine buttons.

The picture behind Mr. O'Neill changes size and color while he is talking to Quinn.

Daria is tan sometimes, pale other times.

Brittany managed to win the contest even though her picture wasn't on display in the earlier scene.

Double Meanings:

None yet.