Michelle Garcia Winner has developed terrific materials, and I have used this book as part of introducing the Superflex and the Unthinkables curriculum to children.
The expense of the books is really offputting to an individual unfortunately, as there are a number of items that are useful to use but they are all quite sparsely filled but with high prices. I'm not sure why this should be, but it's a shame, as it prevents the excellent curriculum from being accessible to more individuals and therefore more children.
If you are working with children with SCD, you REALLY do need to get into this excellent area of work, and make sure you also find out about Superflex and the Unthinkables. If you're working as an individual with just one child the expense may be beyond you - but just hope that the authors find a way to make this more available to those that need it!