A 1975 dissolution decree awarded W custody of the two children and ordered H to pay weekly child support. W's filed a petition to modify on August 15, 1988, at which time the parties' children were eighteen and sixteen years of age. The trial court modified the support from $45.00 per week to $1,043.90 per month when both children are residing in W's home and $522.00 per month for periods when the older child is away from home attending college. This increase was done under Ind. Code § 31-1-11.5-12(b)(1) which authorizes support orders to include college expenses. H contends that the Court of Appeals erred in upholding the constitutionality of Ind. Code § 31-1-11.5-12(b)(1). H argues that the statute is unconstitutionally vague, that it impermissibly treats unmarried parents and their children differently from married parents and their children, and that it infringes upon his fundamental child-rearing rights. Rejecting the claim of unconstitutional vagueness, the Court of Appeals noted the rules of interpretation that favor construing statutes as constitutional if reasonably possible, found that the statute provides sufficient guidelines for a trial court to exercise its discretion, and observed that parents 'seeking to dissolve their marriages are aware that the trial court may, in its discretion, order them to pay for their children's education.' H appealed.