The proper answer is "maybe" because you earned money from CA sources. Take a look at the page 3 of CA 540 booklet
https://www.ftb.ca.gov/forms/2015/15_540bk.pdf
and see if you income falls below the listed filing thresholds.
If you do have to file, you might want to just send in a small payment with their extension form
https://www.ftb.ca.gov/forms/2015/15_3519.pdfwith a check for $20 and file later to get some or all of that $20 back.
Since any refund will be small and your tax situation is otherwise simple, consider bypassing TurboTax for CA and fill in their forms by hand. You don't want to spend $30 to get a $20 refund!
Also, since MO is taxing that $900, you would be due a credit against MO taxes for any paid to CA. I assume you have filed MO by now, so you would need to amend MO later to get that credit. Again, consider handling the MO amendment on your own.
