You can create a testamentary trust via your will, then name the testamentary trust as the beneficiary of your assets. In the trust instructions inside your will, you can name a trustee and a distribution schedule. It's common to dole out money for HEMS (health, education, maintenance, support), college, and then the remainder at certain ages or reaching certain milestones (high school/college graduation, full time job, house purchase).
Even if you don't do anything though, my understanding is that if your child has not attained the age of majority in your state (commonly 18 to 21) if they inherit assets directly, then the probate court will appoint a custodian to manage the funds on the child's behalf until the child reaches the age of majority, so it really becomes a sort of a trust in this scenario anyway.