Even though the price includes a full-size paper plan, by habit, I put the design into Sketchup anyway. Often there are errors in plans, and I often make paper print-outs as patterns. I found no errors in the plan.
I used common 3/4" thick pine to make the blanks for the main assembly. I made a few extra blanks for the marble tracks, so I could sort and throw away any that had bad knots in them.
One could cut these on a router table, but the groove is 3/8" deep, so it would probably take 3 depth passes, then flip the board around and do 3 more passes to achieve a 1 inch wide groove using say a 3/4" diameter straight router bit.
I chose to use my table saw dado set. I can cut the groove to full depth, then flip the board around and do a 2nd pass to achieve the groove width. This method worked great.
The plan calls for making an insert to put inside the track, at one end. My dado set is a cheaper one, and does not make a smooth bottom.......so inserts would not fit very well. Instead, I made a wood cap that fits onto the end of the track, and then glue and pin nail it to the track. This was much faster and works better than trying to fit a piece inside the track.
The plan has a pattern for 2 different templates, that allow you to quickly and easily assembly the angled tracks to the vertical uprights. This worked very well.
My wife had me put bells on similar marble games.........so when the marble drops in the box......it hits a bell (a Wal-mart bicycle bell). She told me no bells on this one.
I liked the 2 decals that came with the kit. I was not going to do any painting..........but decal instructions said DO NOT apply decals to bare wood........so I painted the top and handle yellow before putting on the decals.
This was a fun project to build. The 2 templates are really a great idea, and allow you to build the main assembly prety quickly. The grandkids should have fun with this one :)