At my OLD school, we used Microsoft Encarta 2005.
The Magic School Bus is a series of educational children's books in the US that was adapted in the mid-nineties into an animated television show. The series centers on a class of children whose teacher Ms. Frizzle makes use of the titular magic school bus to take her students on a variety of magical field trips that allow them to experience various scientific topics first hand, such as the inner anatomy of the human body, the effects of friction, what goes on inside a beehive, and many others.
In this comic, however, Ms. Frizzle initially takes the students onto the bus apparently for one of these field trips to explore the way batteries work, but then for whatever reason, she has the students get off the bus again and simply resorts to looking up the Wikipedia article about batteries. The implied joke is that, with the advent on resources like Wikipedia, it's no longer necessary for Ms. Frizzle to take the students on half-hour long trips in the bus to experience whatever phenomenon they are studying that day (which is what the third panel symbolizes) - Wikipedia effectively answers the question quickly and easily. An alternative answer is that Ms. Frizzle has just gotten lazy, and has resorted to looking up the answers to the students' questions on Wikipedia instead of taking them on field trips. The alternative seems more likely, since the third panel shows them still going on an adventure, however briefly it takes to get to the library/computer lab.
The red and white checkered rocket in the bottom-right of the third panel can possibly be a reference to The Adventures of Tintin Destination Moon and Explorers on the Moon, in which Tintin goes to the moon in a rocket that is similar, if not identical, to the one depicted. To the bottom-left is a green Ciliate, a single celled life-form covered in hair-like fibres. At the top right are a set of Planetary gears. To the top left is a ringed planet, perhaps Uranus and in the background is a complex Feynman diagram.
The child who is asking the question looks similar to Wanda, one of the regular students in the class who often asked the questions that set the field trips in motion. Ralphie, the student in the second panel with the backward hat, was another student who often asked these questions. The students in the class were shown to be from many backgrounds (i.e. some of the students were black, another was Asian, etc.), something Randall appears not to have added into this comic, despite it being in color.
The title text is a reference to Phoebe, one of the students in Ms. Frizzle's class, who would regularly make a remark beginning with "At my old school..." (Phoebe used to go to a different school, unlike many of the other students in the class) to express wonder at how unusual were the events of Ms. Frizzle's field trips (e.g. "At my old school, we never rode on bees!"). This was frequent enough for said school to literally mark itself as "Phoebe's Old School" in one episode.[actual citation needed]
Microsoft Encarta 2005 was a digital encyclopedia that was often used in school settings for learning with the aid of computers. Arguably, with the advent of Wikipedia, programs like Encarta have become relatively less widely used, which is part of the joke in the title text.