Catapults are amazing weapons that were mostly used in 14th to 16th century. Catapults have been the most useful weapon for most of the empires. Making a catapult maybe fun but it’s not easy and also it can be very dangerous. Believe me this is not a joke, a catapult can bring a house down if it it used properly.
This relates to engineering by task initiating and using your time wisely. Also being organized and learning how to and which materials to use.