Romola
You have made me feel slightly nervous about the fact that I knit hats, gloves, scarves for all and sundry. And my younger relatives live in jumpers I've made, but not teenage boys except one, who feels the cold.
I know they wear them all the time - unless they put them on specially for WhatsApp video calls.
Take a look at what the trendy male shops have in stock and it’s all hunky, chunky cabled jumpers that look like handknits. Same with lovely hats, gloves and scarves.
Look at the colours they are in and you won’t go far wrong. I am sure they will love them.