Create a parent organizational unit and some children

CreateParentOUAndChildren

# Create a parent organizational unit and some children
Import-Module ActiveDirectory

# Create the parent in dc=domain,dc=net
New-ADOrganizationalUnit "ParentOU"

# Create the children
1..10 | % `
    {
        New-ADOrganizationalUnit -Name "ChildOU$_" -Path "ou=ParentOU,dc=domain,dc=net"
    }