Is he still interested? or is he just shy? idk please help?

ok so im in high school now, and i think i might like this other freshman. the problem is, he's only in my algebra cl, and we dont sit near each other. its a small school, and i still dont see him in the hallways that much. i HAVE talked to him several times, so dont think i didnt. the only time i see him beisdes algebra is in the morning in the hallway but his locker isnt near mine. when i first met him, he was interested. thats why he talked to me in the first place. but now anytime i see him or if i say hi, he doesnt seem interested in talking to me. could he just be shy? and since i dont see him in school all that much, and i dont have his number, or sn, or facebook or anything, should i just give up or keep trying?