If I have them on hand, I'd throw in a Kind bar. They're quick and delicious.
Apples or pears are great for throwing into a bag. I usually wash it at home then put it in a Ziploc bag along with a napkin. Then I just have to grab it out of my bag. Oranges could work too, but they can be messy. Applesauce is great too. They have these nifty little packs now. You just squeeze it like a juice box. No spoon required.
Having a bag of nuts/seeds/dried fruit comes in handy. I try to eat the raw nuts/seeds/fruit since they're healthier for you. For dried fruit, go for the ones without sugar. They're harder to find but are healthier (plus I just think they taste better). I personally love almonds, pecans, walnuts, dried cranberries/cherries, and sunflower seeds.
Whole grain crackers are great. Popcorn is also great. Pop some before jumping in the shower in the morning. Then separate it into bags for a quick snack. Make sure that the popcorn is cooled off first. I know we're in a hurry a lot, but hot popcorn is not something you want in a Ziploc bag. The bag will melt. I learned that the hard way when I was in high school. I was in a hurry and just threw some in a bag after it came out of the microwave. I had to throw out a lot of the popcorn and had kernels roaming around my bag.
Those are my ideas for quick snacks you can just throw in your bag without thinking about keeping them at a specific temperature. If you don't mind bringing a small lunch box, pack some veggies and hummus/carrot dip (Kris Carr has a great recipe I'm dying to try). And always pair a veggie snack with some fruit. Cut up some strawberries or watermelon. Have a cup of grapes or berries. Cherry tomatoes are also great. Don't forget, tomatoes are in fact a fruit!
All my suggestions are based on my favorites and what I've found convenient.
What are your favorite snacks?
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