De vs en
 

Can ‘del’ be replaced by ‘en mi’ or ‘en el’?
• El equipo del colegio
• El equipo en mi colegio

If you want to express belonging, you can only use "de":

- El equipo del colegio. (We know what school you're talking about.)
- El equipo de mi colegio. (A bit possessive if we already know which team you're talking about, but fine.) ;)

- El equipo en el colegio. (It doesn't necessarily express a sense of belonging or that it represents the school, just that it was formed there.)
- El equipo en mi colegio. (Same as previous, but this time we know it's your school for sure.) :)

If you use "en" you could potentially be talking about a team that is merely at the school right now, but is not the school's team. Of course, that's assuming you mean team and not equipment. :)

Much appreciated, thanks.