A screensaver with animals in a moonlit meadow
Animals in the dark in Screensavers by Zaweba has cartoon frogs, rabbits, deer and bees crossing a moonlit meadow with fireflies, up to 16 at once.

Animals in the dark, in the night pack of Screensavers by Zaweba, is a moonlit meadow where cartoon frogs, rabbits, deer and bees hop, graze and buzz while fireflies drift about. You choose how many animals appear (from 1 to 16), which kinds, how fast they move and how bright the night is. One thing to know up front: the animal art is placeholder drawings for now, until real sprites are supplied.
So it's an honest answer with a small caveat. The screensaver works and is pleasant to watch, but the animals themselves are simpler than they will eventually be.
What happens in the meadow
Frogs hop, rabbits hop and graze, deer graze and wander, and bees buzz between them. Fireflies blink across the meadow the whole time, which is often what people enjoy most: small points of light on a dark screen, never still and never bright enough to dazzle.
Like the rest of the night pack, it's mostly dark with a few bright moving things, so it's comfortable to have on in a dim room.
Choosing the animals and the night
The number of animals runs from 1 to 16. One lone deer makes a quiet, almost wistful scene. Sixteen fills the meadow with activity. Which animals lets you leave some out, so you could have only frogs and fireflies for a pond feel, or only deer for something calmer. Speed sets how lively they are. Night brightness decides how much of the meadow you can see: lower is moodier and closer to a real night, higher shows more of the animals.
The live preview in the manager follows each change, so try a few combinations and see which you'd like to come back to.
About the placeholder drawings
The current animals are placeholder drawings. They show where each animal goes and how it moves, and they're drawn in Zaweba's own code like everything else in the pack, but they're simpler than finished artwork. When real sprites are supplied they'll replace the placeholders. If you install the screensaver now, you're seeing the scene as it works today, not a finished picture book.
For many uses that's fine. Children often enjoy it as it is, and the fireflies and moonlight carry the mood.
Getting it onto the screen
Open Screensavers by Zaweba and choose Animals in the dark. Set it up while the live preview plays, then press Preview full screen to see the meadow at full size; a deliberate mouse movement, a key or a click brings you back. Press Use this screensaver to build it into your Windows profile, without administrator rights. Windows' Screen Saver Settings opens so you can select it and set the wait time.
Change the animals later whenever you like. Each screensaver reads its settings when it starts, so nothing needs rebuilding.
In a child's room or on a family PC
A low night brightness, a handful of animals and a slow speed make a gentle screen for a child's computer in the evening. If the PC has more than one monitor, the several monitors setting lets you run one on each, stretch one across them all, or keep it on the main monitor with the others black.
To mix it with other night scenes, tick it along with Growing foliage or Deep space and use Install several. You get one screensaver that picks one at random each time the PC goes idle, so the meadow turns up as a nice surprise rather than every single time.
Everything runs offline, as free software under the EULA, with no account and no adverts.