Get your teacher to show you how to play in tune (if you have a teacher), someone showing you and explaining things step by step is a great help.
Like Jacobi said....in 1st position, check your third finger against the string below, and you can check your fourth finger against the string above (of course make sure your violin is tuned properly, if it has new strings, it will go out of tune even every minute you play, you might have to tune it twenty times or more during your first practice session after new strings are placed).
So, third finger on D string is a G, listen to the sound you get from 3rd finger on D then listen to the sound the sound you get from open G, of course the G you get from 3rd finger on D string is an octave higher but it will still sound like a G.
For fourth finger on D, this will be an A so you can check it against the open A, these 2 will be exactly the same.
Play the scale in the key your piece is on several times before you play the piece, very slowly, listening to the sound you get from each note, again when playing the scale check against your open strings, is Ode to Joy in A major?? (can't remember), if so play A major scale (it's either A major or D major being a grade one piece

)
Also play the arpeggio many times over before you play the piece.