This is an Iron Man head I carved out of balsa. From chin to crown, it is about 145 mm tall, and about 90 mm wide at the widest part. It weighs about 150 g (a little over 5 oz.).
Step 1: Balsa block glue-up
I purchased blocks of balsa from a craft store and glued them all together as shown with wood glue. The individual blocks were approximately 3" x 5" x 1.5". When the glue was cured, the large resulting block was trimmed so the final dimensions were 6" x 5" x 3.5".
I made a side-view template of Iron Man's helmet by tracing a side photo of an Iron Man toy using basic drawing tools on my computer. I've included a PDF of that template just in case you are so inclined to make one of these.