Snacks such as, mixed nuts, almonds, cashews, and peanuts. Each of these pack a lot of protein. String cheese is another great healthy snack idea. String cheese is also a good source of protein; as well as calcium.
For more great healthy snack ideas, see this site.
This site tells you 5 healthy snacks that you can enjoy and snacks to avoid at the same time. Some of which include Oatmeal, Nonfat Greek Yogurt, Low fat string cheese with fresh fruit. Oatmeal is high in fiber, while nonfat Greek Yogurt is high in protein. But, it’s best to avoid snacks like crackers and chips. For the full list, check out this site.