Hi! Newbie question re: seedlings!

Hi! Newbie question re: seedlings!

Hey everyone! What a wonderfully helpful community! Thanks for being here! Now, my question: First, background: I bought some marigold seeds on a whim, and decided to help them become flowers. To do this, I made my own little seedling starter by cutting an egg carton in half, poking holes in the bottom of the cups and putting the top half under the bottom for drainage. I also re-purposed some plastic packaging as a little cover for the top, tiny greenhouse style. It's only covered on the top and sides, not on the short ends, so there's some air flow. The actual question: Can I leave this outside to germinate (watering every day)? Or should I move it inside? It's hot as H-E-doublehockeysticks outside (I'm in Texas.) BUT I'm not 100% sure that my curious kitty won't knock the whole thing off the windowsill if I leave them inside. So. Seedlings--inside or out? Discuss. Thanks! :)
Terrarium.

Terrarium.

Introducing myself

Introducing myself

What’s this new visitor?

What’s this new visitor?

Picture Hanging Help!

Picture Hanging Help!

OY VEY

OY VEY

Pics of the living room.

Pics of the living room.