For full disclosure, we own SIX of these 24-piece jigsaw floor puzzles by Petit Collage. They are well made, high quality, great large size pieces, and are perfect as floor puzzles. We use them with toddlers and pre-schoolers but could probably be used through first grade if desired. The pieces are cardboard and paper so they are not meant to get wet, be chewed upon, etc. Only use the puzzles with kids who have clean, dry hands and don't put the pieces in their mouths. Overall, I suggest that toddlers start with Petit Collage's beginner puzzles then work up / scaffold up to these 24-piece floor puzzles. The best 24-piece floor puzzle to start with is Our World (see reasoning at end of review). Use: With younger kids or students with learning delays, I start with separating the edge pieces from the internal pieces. I then have the child work on putting the edges together, focusing on colors or objects that would be in common. Grouping similar colors or objects together usually enables a faster matching process. Then I give the child the inside puzzle pieces to finish the puzzle. They can be matched to the edge-piece frame by looking again for similar colors and objects. I often have to remind kids that objects should be upright not upside down. Once a child has mastered this two-step process (edges then internal), its time to let the child separate the edge pieces for themselves to complete the puzzle. At first the parent or teacher may need to be present to remind that edge pieces have 1-2 flat sides and correcting as needed. The parent/teacher may also need to remind the child to make the edge frame first then do the internal pieces. Once a child has mastered completing a puzzle from start to finish with your monitoring, it is time to let them do the puzzle on their own. The child may go against the edge then internal structure, but that is ok as long as the puzzle is getting done (I mean there is more than one way to do a jigsaw puzzle right). BTW - older children or extremely able children, they will not need this degree of scaffolding - you probably could just hand them the box and let them figure it out through problem solving. The very young or challenged may not have the problem solving skills yet to tackle a puzzle on their own - so you need to teach them HOW to problem solve and useful strategies before they can do it on their own. The six puzzles we own are: Construction Site, Our World, USA map, Wild Rainforest, Enchanted Forest, and Farm. Here are some specs on each of them. 1. Our World floor puzzle is color coded by continent, which divides the puzzle into separate color areas. This makes it much easier for three year olds to place the jigsaw pieces. The puzzle also enforces learning of the continents, though Greenland being a different color than the rest of North America might confuse some kids. I highly recommend that you start with this puzzle before moving onto the harder ones. 2. Construction Site has silver, shiny, metallic areas which make the objects pop. My three year old loved that detail. 3&4. Both Wild rainforest and Enchanted forest were the hardest for three year olds to do because there is a lot more going on.. and a lot of similar colors. The kids were really motivated by the images in the puzzles, so they did complete the challenge. 5. The Map of the USA is educational and a tad harder than the Our World puzzle. This is because the colors are more pop corned all over the place (so its harder to tell where pieces go unless you already know the states and what they look like.) Start with learning the continents and the Our World puzzle, then work to doing the USA map puzzle. 6. The Farm puzzle was overall the least interesting of the puzzles we purchased (at least to toddlers). They wanted to put the puzzle together, but once made, they just wanted to put it away - whereas they begged to leave out the other puzzles so they could look at for a while. It is still a wonderful puzzle, it is just that the images were not as engaging/exciting as the other puzzles we have.