Both shows are really fast-paced comedies who revolves around school girls doing random stuff. Also both of them are quite short and have no plot.
In short, they are so similar that if you liked one of them you're going to like the other.
Both shows are shorts that are filled with chaotic, random humour. The viewer gets bombarded by jokes one after another without pause, with absolutely zero time spent on any meangingful plot.
If you enjoyed one of these shows then the other will definitely be to your liking.
In present day Japan, the life of a school girl is never dull. The easily-bored Konata never finds time to study because of her otaku habits, which frustrates hard-working Kagami to no end. On the other hand, laid-back Tsukasa always manages to go with the flow, while Miyuki is concerned with keeping her status as resident know-it-all. Join these four girls as they muse and meander their way through everyday events such as eating chocolate cones, doing homework, gaming, and trips to the beach galore.
Play Lucky Star on fast-forward and you have Teekyuu. Both have random comedy and little plot (zero plot in the case of Teekyuu). I think if you enjoyed one you might be interested in the other.