What was the significance of the two angelic figures that faced each other on the Ark of the Covenant appearing as children?
The two angelic figures you refer to, the cheruvim, were part of the lid of the Ark in which was placed the tablets of the Ten Commandments. These figures, as was the entire lid, were made out of solid gold. The faces of these figures were child-like, one male and the other female, who faced each other and whose outstretched wings hovered over and joined above the Ark.
This loving pair paralleled G-d and the Jewish People, representing the special, loving and devoted relationship between them. The faces were fashioned with juvenile purity to convey the idea that only when Israel was pure and free of sin would they enjoy the close, loving and devotional relationship desired by G-d.
In fact, the sources state that when the Jewish People distanced themselves from G-d, the faces of the figures would miraculously turn away from each other commensurate to the degree of Israel’s straying. When they repented, the faces of the cheruvim would then turn back to each other according to the degree of repentance.
Since the Ark upon which the cheruvim were fashioned contained within it the Tablets representing the Torah, and since the Ark and its child-like cheruvim were located in the inner-most section of the sanctuary, this establishes the sanctimony and centrality of children in Jewish education.
Apropos of this, despite the fact that all were commanded to be involved in the building of the Temple, children’s Torah study was not to be interrupted even for this most important of mitzvot!
When Rabbi Meir Shapira was in the process of building his very important yeshiva “Chochmei Lublin” he traveled far and wide to collect for this important project. He once noted that the various instruments used in the Temple could be made of any metal if gold was not available. The only exception to this was the cheruvim, which must be made only of gold.
The explanation he offered for this distinction is as follows: The cheruvim represent the precious importance of connecting Jewish youth to the Torah. And when it comes to achieving this paramount goal of providing for and ensuring a proper Jewish education for our youth, no inferior alloy will do. Rather we must be prepared to demonstrate our mettle by giving in gold!