How do I help a struggling student with big gaps or anxiety?

You can reach most students now. It is the ones with deep gaps or real anxiety who still stump you, and no wonder, they are the hardest cases anyone faces. A student who is scared or far behind cannot just be taught the material. Something has to come before the learning. With these students, the content is not the first problem. The fear is, or the shame of being behind. Until that eases a little, nothing you explain will land, because their mind is too busy protecting itself to take anything in. Your job shifts from teacher to something closer to steady, patient guide. Next session with a struggling one, spend the first few minutes not on the subject but on them. Find one thing they can already do and let them feel it. Lower the stakes out loud: tell them it is okay not to get it yet. Safety comes first, then learning follows. Start there and watch what opens up.