Practicing is tough initially, but the more you work on a section carefully and slowly, the better it will go in the long run. Playing through a piece or section many times will not help you learn it better. When in doubt, try and come to Mrs. Creamer for extra help during Flex blocks, or early release Wednesdays
Start your practice by playing the scale carefully and accurately that corresponds with the piece
Practice 2-4 measures at a time (depending on difficulty)
You can even play just a group of three-four notes depending on the piece (plus one extra for connecting the passages)
Try the following steps...
Say note names rhythmically and move your fingers
Pizzicato
Bow without expression (accents, slurs, dynamics etc.)
Bow with expression
Practice the sections/measures a minimum of five times before moving to the next step/measure/section
When struggling with coordinating fingers and bow...
... try pizzicato to improve your knowledge of the fingers
... try bowing the open strings to improve your knowledge of the bow
Then put them together
Start with the last measure/two of a piece and work backwards, practicing the previous two measures and then combining with the last two
Try rhythms to help learn tricky passages with even numbers of eighth notes or sixteenth notes
Long - short - long - short
Short - long - short - long
Long - short - short - short
Short - short - short - long
Learn notes by playing the note, repeating it and slurring to the second note, repeating the second note and slurring to the third note, etc.
Sing your part and then try and play it while you sing it (then try and play it while you hum it or sing it in your head)
When learning double stops...
Play just the bottom note (with the correct fingering)
Play just the top note (with the correct fingering)
Play just the bottom note but place your fingers as if you were playing the top note
Play just the top note but place your fingers as if you were playing the bottom note
Play it as it's written
When learning a shift, add a guide note (first finger)
Play the note before the shift
Play your first finger
Play your first finger in the new position
Play the note you're supposed to shift to
Once you can do that successfully, then makes steps 2 and 3 silent
Once you can do that successfully, then remove steps 2 and 3 and play as written
If you're struggling with a particular rhythm (dotted quarter for example) play the subdivisions (play the dotted quarter as if it was three repeated eighth notes)
Here is a great video that helps you understand certain practicing tricks. Under the poster's name you will see links to skip ahead to different sections if you want to learn a specific trick.
Cellos! Here is a great video that helps you understand how read tenor clef. The first few minutes are the most helpful!