ACT without Writing useless if schools want Writing section?

I am a sophomore and I took the ACT and got a 35. However I took the ACT without writing and I saw that most colleges require the ACT Plus Writing. Does this mean that my ACT score without writing is useless or is there some way for me to take just the writing? I am planning to go to either Michigan State University (MSU) or MIT, and both of them ask for the Writing section.

You can send these colleges the score you got without the Writing section, but you'll also need to take the ACT again with Writing. There is no way to take the Writing section without also taking the multiple-choice portion of the ACT.

Ideally, when you take the test again with Writing, you'll get an identical or similar score, so you won't need to send both results. If your second composite score ends up being two or more points lower than your first one, however, you should send both. You just need to have at least one test that includes the Writing section.