Keep it up without drugs!

Keep that older sash window up at whatever height you want it with this drug-free tip.

Drill a few holes into the jamb, and insert a finishing nail (circled) as the keeper of height.

Beats using a stick!

With the sash closed, drill another hole at the top.

Put the keeper there when the window is closed. You'll know where to find it, and it helps to secure the closed window from forced entry.

For extra security, you could do the same on the other side as well... or you could just move, if your neighbourhood is that rough.

See also:

Restoring sash windows

Painting the hidden exterior strip