Quick question about weak stems

Hey first time grower here and I have a question. My plants are around 4-5 inches tall (I have about 10 of them) and I've noticed recently that some of them need help standing up straight. I used a small, slender piece of wood to prop them up and I guess it's no big deal but I'm wondering if there's a point in the growing process where I don't need to prop any of them up? They've been growing probably a little under 2 weeks, and I've had continous 24 hour a day light on them. I'm probably going to be switching to 18/6 within the next 2 or 3 days, will they start to strengthen at that point? Or am I doing something wrong? Thanks!

Oh ya forgot to mention that i do have a small oscillating fan going in my room, but I leave it on low, because when it's on high me plants get too battered.

Get some fans blowing on those babies ASAP! This will help promote healthy strong stems.

What kind of lights do you have on them right now. Im not sure cause theres no pictures but Im gonna guess that they are stretching, if the stems are too thin to stand up. Maybe move your lights closer. Also get the fan blowing on them like grnman said.

get a desk fan and hang it or set it above your plants blowing down on them on low speed. enough to see thee plants moving a bit. keep the supports for the plants that are leaning and in a few days youll be able to remove them and they should stand up straight!