Select green beans to freeze. Choose young, tender beans with a bright green color and firm, crisp pods that snap easily. Rinse your green beans in cold water, discarding those showing blemishes, wilt, decaying spots or bruises.
Snap the stem ends off of your green beans. Pull off the strings, if needed. Snap the beans into 1- to 4-inch pieces. Sort the green beans according to size. You want all your beans to be about the same size so they all blanch in the same amount of time.
Bring a pot of water to a boil. Use 1 gallon of water for every pound of green beans. Put your beans into a blanching basket. You can also use a wire basket, a cheesecloth sack or a metal colander. Gently place your green beans into the boiling water. Let the water return to a boil and set your timer for three minutes.
Cool your green beans immediately after blanching them. Place your beans in ice water and allow them to soak for three minutes to completely halt the cooking process. Pour your green beans into a colander and let them drain thoroughly.
Pour your green beans into airtight plastic containers or baggies. Pack the beans tightly and leave about 1/2 inch of headspace. Label and date the containers and immediately stick the green beans in your freezer.