get (someone's) hopes up

to make someone think that what they want is going to happen.

If we can't afford the trip then we shouldn't get the children's hopes up.

Usage notes: usually said when something is not likely to happen

• have done more than someone has had hot dinners
• have [done/seen/had etc.] more something than has had hot dinners
• have [done/seen/had etc.] more something than someone has had hot dinners
• have [done/seen/had etc.] more than has had hot dinners
• have [done/seen/had etc.] more than someone has had hot dinners
• have down on like a ton of bricks
• have down on you like a ton of bricks
• have down pat
• have down to a fine art
• have down to a science
• have ducks in a row
• have ear
• have ear to the ground
• have egg on face
• have egg on your face
• have end away
• have eye on
• have eye on someone
• have eye on something
• have eyes in the back of head
• have eyes in the back of your head
• have eyes like a hawk
• have feet on the ground
• have finger on the button
• have finger on the pulse