Nine of the DMC’s fifty-five sections detail the proclamation and preaching of the Word. Rome considers this important for children, clearly.
41. Since readings taken from holy Scripture “form the main part of the liturgy of the word,” [GIRM 33.] even in Masses celebrated with children biblical reading should never be omitted.
42. With regard to the number of readings on Sundays and holy days, the decrees of the conferences of bishops are to be observed. If three or even two readings appointed on Sundays or weekdays can be understood by children only with difficulty, it is permissible to read two or only one of them, but the reading of the gospel should never be omitted.
I find the number of readings less a problem than the disconnect we often have in the Sunday and daily Lectionary cycles. There is something a bit ADD in a separate running theme of readings in weekday Ordinary Time and in Sunday’s New Testament reading.
In working with school liturgies, we always use two readings, never one. It is really the burden of the homilist to make sense of the readings. If a homilist were unwilling or unable to address a potential point of misunderstanding in a reading, it probably should be omitted.