Clip-on tuners are suggested for each student to keep in their case for use at home and school. Tuners can be purchased at local music stores or online retailers. Snark and D'Addario are recommended brands. A fun character version can be found at Aloha Tuners. Remember to mark your name on your tuner!
The violin, viola, and cellos videos below cover how to use a tuning app and fine tuners, then about half way through will cover how to start tuning with the pegs if necessary. Basses don't have fine tuners and will only use mechanical pegs.
Violin
Viola
Cello
Bass
The links below provide additional info and tuning pitches if you want to hear the sounds of your strings. There is also other helpful info and resources on these sites.
Violin https://www.violinonline.com/tuning.html
Viola https://www.violaonline.com/tuning-viola.htm
Don't worry - it's okay! This happens and can be fixed. Go to Popplers Music or contact your specific vendor. They can help you put on a new string or assist you in purchasing a new string.