A more advanced "Eco" version with 39 press-out parts. It features an extendable telescopic tube and is better for older children (8+) who want a more complex building experience. You can find it at eBay for around $31. BrainStorm Periscope STEM Kit - Individual Kit STEMfinity Go to product viewer dialog for this item.
A straightforward, hands-on learning kit priced at $9.95 through Macs & Milli . Bulk & Classroom Options Periscope Classroom Kit Arbor Scientific Go to product viewer dialog for this item. cardboard periscope buy
: If this is for school, kits that include lesson plans or worksheets (like the TTS Class Kit ) provide better value. A more advanced "Eco" version with 39 press-out parts