If I understand correctly, consider using the 'Match()' JSL expression. I generated the code below by using 'Cols > Recode':
![Screen Shot 2018-09-03 at 15.29.02.png Screen Shot 2018-09-03 at 15.29.02.png](https://community.jmp.com/t5/image/serverpage/image-id/12288i7F31C4A8A273AE18/image-size/large?v=v2&px=999)
and inspecting the JSL for the resulting formula column. And, 'yes', JSL is very different from VBA. You should look at 'Help > Books > Scripting Guide' and/or consider some training.
NamesDefaultToHere(1);
dt = Open("$SAMPLE_DATA/Big Class.jmp");
Wait(3);
dt << New Column( "Age 2",
Character,
"Ordinal",
Formula(
Match( :age,
12, "Twelve",
13, "Thirteen",
14, "Fourteen",
15, "Fifteen",
16, "Sixteen",
17, "Seventeen",
Format( :age, "Fixed Dec", 5, 0 )
)
)
);