I worked in a school with cinderblocks and it was really tough to get stuff to stay. I remember having an awesome display for the hallway and it kept falling down! I finally hot glued it, but then some of the glue was tough to get off.
Believe me, I've tried everything (packing tape, glue gun, that blue sticky stuff at teacher supply stores--"tacky" something, picture hanger adhesives, even chewing gum!) and the only thing that reliably works is velcro. They make in packages with the pre-cut dots, but the strips on a roll are stronger and cheaper. It really works, believe me! I not only have cinder blocks, but it's had about 10 coats of paint on it. I also have a very old, very strong air-conditioner blowing toward the wall, and nothing ever falls off, the whole year!
I've had success with the wide, clear, packing tape (not the kind with string running through it) like librarians use. I can find it at dollar type stores for under $1.00 a roll and always keep spare rolls in my desk since everyone else borrows it. The stuff works. Posters and artwork come down when I want them to, and the tape leaves no sticky residue.
Good luck and congrats on your job!
I use hot glue on mine. Things rarely fall; some have been up for years, like my alphabet. Sometimes the glue can be hard to remove. The only time it's caused a problem with the paint is when I've tried to scrape it to get it off. I heard somewhere this summer (probably here) that avoiding multi-temp and low-temp guns and glue sticks can help--which is what I've been using.
Love the stuff...admin could believe that is what I hung all of my items with!! I have cinder block wall, paint boring white!! So I hang alot of stuff. Make sure everything you have is laminated. The duct tape peals nicely off lamination. I even hung plastic table cloths from ceiling with duct tape.
I second the blue sticky-tack. I use strictly the Handi-tak (I think that's how you spell it) brand. I have a ball of sticky tack I have used year after year for over 14 years. I can stick something up with that stuff and it'll stay all year. Laminated things work better especially since the stuff comes off easier and I always reuse. Sometimes my students ask to keep the sticky tack when they help me tear down or put stuff up, and I always have to smile and let them know I literally use it over and over and over again. I originally used blue, and then could only find yellow and now my tack ball is GREEN and works even better than it used to. I think it's the dirt and oils of mine and the kids' hands that adds to the sticky effect. Be sure to put it on all corners and sides and parts that stick out etc....I roll it into a small pea-size ball and attach it to the back side. Then, when you stick it to the wall use lots of pressure and be sure to push hard on all spots that have the tack on the back. I SWEAR by this stuff and never any troubles getting it off the wall or pealing paint or upset janitors or principals!
I agree with the "blue"- I've used it for years and this year I had trouble finding it, so I got some from Staples.......I'll try that and see how that works. Getting ready to put up stuff this week and next.
For my posters and things that stay up all year I used 3M Command strips. Nothing fell down, even my calandar that get pulled on a lot with changing dates and all. I have also used a tape called Mavalous (sp) they sell at teacher stores or at least in CO.
the only thing I have had success with is the stikki clips. To hang posters, I put the clips around the four corners. They stay up all year! I left the clips on the wall (just popped the posters out) so I am hoping they are still hanging on the wall when I get back!
Here is what I have found because my ciderblocks get damp and the blue tack doesn't work. The 3M tabs that are used behind those plastic hooks. I cut them down the center so that I can use one tab for two corners of the poster. I know that they are expensive but it is well worth not having posters fall down every day!