Each trust is about a 5 page document, identical except for the names. It specified the limited uses for the funds, namely post high school education, but could also be used for emergency health or welfare of the nephew in the sole discretion of the trustee. We signed it & filed it with the IRS, along with applying for a tax ID number for each trust. At the time, we needed to have the nephew's parents (my siblings) sign a simple document that they agreed to the trust accepting our gift rather than them for their minor child -- in reality, no agreement, no money. Then we funded each, using the trust title & ID number to style the index funds. Every year I filled out & filed a Form 1041 Income Tax for trusts, which wasn't hard to do. Since the trust was intended to retain annual earnings & appreciation, no K1 needed to be sent & the IRS considers this to be a "complex trust". The trust was required to pay taxes annually (quarterly if over a specified amount) but in our case this was either 15% or nothing if the gain came from appreciation rather than a distribution. I used two index funds: Vanguard Total Market Index Fund, and Dodge & Cox Stock Value Fund; both did well but Vanguard did better. The nephew did not have to pay any tax since the trust already did.
While an educational trust is considered an asset of the student, even though he cannot touch it, the fact that our trust language called for any residual to be held until age 30 if the beneficiary did not graduate from a 4 year university or equivalent vocational school should exclude most or all of it from the FAFSA. You will want to confirm this.