This scenario has been a delight to read through so far, and I particularly like that it is much more lighthearted than a lot of other Call of Cthulu scenarios I've read before.
The premise of St. Dymphna's Orphanage: Azathoth's Children is simple, allowing the keeper to focus on creating a space for their players to roleplay together in and encouraging a bit of fun and creativity (think: Roald Dahl's Matilda).
With the handouts for investigators to discover as they learn more about the mystery at the orphanage, there will be enough to keep my players engaged in the mystery and its breadcrumbs without me needing to keep track of too many things. This will definitely be in my favor as a newer Keeper, and allows me to focus on the setting and enjoy riffing with my players.
The document is clearly laid out and easy to read, with keeper's notes and recommendations for play and roleplaying hooks to keep your players engaged - both for your proactive players, and any players that might be more passive.
I haven't yet had the chance to run this scenario, but as a one-shot it is going to be just perfect to run for the next time my group and I get together, and we are looking forward to it.
I would definitely recommend you pick this one up and try it out as there is very little prep for it required, given the simplicity in its playful premise.