Filing returns for my children's trust accounts for college

We have 2 kids.  Each of them has a trust fund that was set up in 2018 when my father passed away.  These funds are for college savings.  I know I have to use forms 1041 and K-1 for tax preparation, but what form(s) do I use to file the returns for each of the 2 children?  Can this be done using 1040 or 1040ez?

Thanks in advance.