You can try to do a few surveys if you are very free during your week offs. Sometimes, it can be frustrating to be told that you do not qualify or survey closed after spending a few minutes to answer their initial questions.
If you understand that and still want to try a few surveys here and there, you can try.
Doing couple of extra shifts during your week off is a better way of earning extra money than doing these surveys but if you really do not want to do any extra shift, these can be tried.
I do not have any affiliation with any of them. Try them on your own will.
I will add good ones in future based on feedback from others.