Yes, valuations are placed on people at various ages, determining their work worth. Lev 27 speaks of the value of various age groups, male and female, a month to 5, 5 to 20, 20 to 60, 60 to death.
The Lord said to Moses, 2 “Speak to the Israelites and say to them: ‘If anyone makes a special vow to dedicate a person to the Lord by giving the equivalent value, 3 set the value of a male between the ages of twenty and sixty at fifty shekels of silver, according to the sanctuary shekel; 4 for a female, set her value at thirty shekels; 5 for a person between the ages of five and twenty, set the value of a male at twenty shekels and of a female at ten shekels; 6 for a person between one month and five years, set the value of a male at five shekels of silver and that of a female at three shekels of silver; 7 for a person sixty years old or more, set the value of a male at fifteen shekels and of a female at ten shekels."
Mind you, these are values reflecting the value of physical work--not measures of worth to God. All Israel, at a time when it was divided into 12 distinct tribes, all had equal value represented by different precious gems on the high priest's breastplate. Men had slightly more value than women. Young people above 5 had more value than old retired people, but even retired old people had significant work value. What value there is in an infant one month old I don't know? I shouldn't think there was any work value at all? So for babies the value had to be something a little less than work? Perhaps it was an investment in their potential future work value, since that may be willing to continue in service?
Beyond this I should probably add that there are ages at which a person would begin to serve in the military or as a priest. This accounts for a certain level of maturation and experience in life. 20 and 30 years of age seem to be important.
