Idiom: to have a blast
Example 1- (last week) Don't forget to buy your ticket for the Beach Party! It's and we always have a blast, so you don't want to miss it!
Example 2- (this week) The Beach Party was so much fun! We had a blast playing beach volleyball, tug-of-war, water games, and the ALS Ice Bucket Challenge! I'm so glad I didn't miss it! I can't wait for next year.
Meaning: "to have a blast" means to have a lot of fun.
Grammar note: the verb have changes according to the necessary verb tense:
We will have a blast next week.
We had a blast yesterday. @LSINE @LSIOC
We are having a blast right now. @LSISB @LSILA
See all the #LSIBeachParty14 pictures on Picasa at https://plus.google.com/photos/102773294412586155497/albums/6054915585057002849?banner=pwa