[Edit: The offer for these modules has expired, but they remain tried-and-true investments if you're looking for low-level adventures.]
Wizards of the Coast has been offering for the last weeks a rotation of free D&D 5e modules an images as part of their COVID-19 support initiative, including some modern classics from the Adventurers’ League like Tales Trees Tell and The Scroll Thief. You certainly can go check it all out, but I’ve highlighted here 5 must have modules from the current offering. These have all received great accolades and can serve to expand current hardcover offerings or your own world. Check them out before they disappear the 17-18th of May.
Pudding Fairy - A 3-4 hour module for character levels 1-4.
You awaken on the morning of the Pudding Faire: just as you did yesterday… and the day before that… and the day before that! To escape the loop, you must break a curse that strikes to the heart of halfling and gnome lore.
Blue Alley - A 3-4 hour adventure for characters of 1st to 4th level.
Blue Alley lies hidden in the heart of Waterdeep. Built by a secretive wizard, it is a magic maze full of tricks, traps, strange monsters, and rich treasure. Countless adventurers have ventured inside to test their bravery and skill, yet few have returned. And now it is your turn…
The Black Road - A 2 hour adventure for 1st-4th level characters.
Caravans are having a difficult time getting through to Parnast via the Black Road. Little do they know that an unusually intelligent hill giant, going by the name of Bad Fruul is to blame. SEER has sent her emissary Hsing, to task your group to accompany a caravan with a very special cargo destined for the Shrine of Axes in Parnast, and to figure out who is responsible.
Uninvited Guests - A 2 hour adventure for 1st-4th level characters
The Shrine of the Axes has been restored and Raggnar Redtooth, who previously conspired with dragon cultists, is trying to restore his reputation in Parnast by sponsoring a feast. There is just one thing he needs, meat for his feast. Game is supposed to be plentiful in the Weathercote Wood, but the townsfolk are all busy with their own work, and the minions of Bad Fruul are still out there causing trouble. What can go wrong on a simple hunt?
Rats of Waterdeep - A 3-4 hour adventure for 1st-4th level characters.
Solve a brutal crime on the mean streets of Waterdeep in this madcap companion adventure for Xanathar's Guide to Everything! Includes two new NPC villains: the Rat King and the Lady of Plagues, and three new player options: the Detective background, the Rat King archetype for rangers, and the Circle of Plagues archetype for druids.