I've been playing the violin for about 2 years now, and my family says there is a sound coming from it that sounds kind of scratchy, but I don't hear it when I'm playing it. Is the scratchy sound because I didn't put enough rosin on the bow or maybe is it the temperature change?
The "scratchy" sound may not be from your instrument. Depending on what instruction you have received, the scratchy sound may be a technique issue with your bowing. It is common in many learners of the violin to apply too much pressure to the bow stroke, or not have enough movement of the bow hair across the strings, which will produce a scratchy, grinding sound.
If possible, you should seek the advice of your Orchestra director, an experienced private instructor, or a clinician to check your bow hold and technique.
Until you can find an experienced player or instructor to check you technique, try making sure your bow hold is relaxed and not gripping, that you are not pressing down forcefully on the bow, and use as much bow length as you can for each note to see if that improves the sound.
Bowing from the shoulder and not the elbow, as well as not keeping the hair parallel to the bridge may also produce some unwanted sounds.
You should bring your violin to a professional luthier, or look at youtube videos and change strings, rosins, bows and bridge. Set all these things a proper way; the majority of cheap instruments sound bad no matter how virtuosic you are. Good things have a relevant price, you know. However, surely if you are not proficient in playing, the most expensive violin in the world will not make you a star.