i am still hungry ugh

Are you eating enough protein and fiber? That's what will fill you up. Are you eating whole grains, instead of white, processing flour? That too will fill up up. Are you drinking enough water through the day? If you are not, try drinking a full, 8 oz glass of water before you eat lunch. A lot of times we mistake thirst for hunger.

Your question is pretty basic and kinda broad, but check into those above factors first. They should help.

Good luck!

wait a while and drink some water. if you're still hungry after another hour or so, then have something small and full of fiber, drink more water. wait.

i'm assuming, of course, your lunch is reasonable

Agree.
Wait 20 mins. I bet you don't even need the water. Your body can take that long to feel full. So if you wait that long and are still hungry, try something like a serving of almonds or fruit/veggies. That should help you curb your hunger.

Just something to keep in mind - did you eat something you LIKED? I mean, I've found that if I eat a blah sandwich with blah carrot sticks, then I tend to feel hungry after (though it's probably all mental). Sometimes perking it up just a little - spicy mustard/a little coleslaw on my sandwich/hot peppers or even a little veggie creamcheese instead of mayo, is just enough of a difference to make it more satisfying so that I'm not craving food after. My other trap is that I'm hungry because I'm bored or don't want to go on the next activity and eat more to put off doing it. Just things to be aware of. Good luck!