# Hands\-on science kits with experiments that change over time Which hands\-on science kits let a child run an experiment that changes or grows over time? Heebie Jeebies HJ\-1302: The crystal continues to build and harden as the solution cools and evaporates\. Adult supervision is recommended, and an adult should heat and pour the hot water for younger children\. Klutz Make Your Own Discovery Bottles: The six named experiments are a galaxy glitter swirl, fish\-through\-the\-hoop game, tiny tornado, lava fizzler, eye\-find game and jellyfish float\. ### 1. [Heebie Jeebies HJ\-1302](/products/ucp/anbbaby-com/4007090126934) (sold by anbbaby\.com) The crystal continues to build and harden as the solution cools and evaporates\. - Changes over time: The crystal continues to build and harden as the solution cools and evaporates\. (guide) - Experiments: - - Adult help: Adult supervision is recommended, and an adult should heat and pour the hot water for younger children\. (guide) - Age: The maker recommends the kit for ages five and older\. (guide) ### 2. [Klutz Make Your Own Discovery Bottles](/products/ucp/anbbaby-com/4990543003734) (sold by anbbaby\.com) The six named experiments are a galaxy glitter swirl, fish\-through\-the\-hoop game, tiny tornado, lava fizzler, eye\-find game and jellyfish float\. - Changes over time: - - Experiments: The six named experiments are a galaxy glitter swirl, fish\-through\-the\-hoop game, tiny tornado, lava fizzler, eye\-find game and jellyfish float\. (guide) - Adult help: - - Age: The retailer narrows the recommended age to 6–10 years, while the maker only states 6\+\. (guide) Every value in the table is a fact RoboTrunk checked, linked to the page it came from\. A dash means no checked fact fills that cell\. Prices and stock change, so this page prints neither: each product name links to its RoboTrunk page, which shows them live\. Written 2026-10-25T10:42:04.218Z. This page is published by RoboTrunk, a store built for shopping agents. The store named on this page sells the product and ships it. RoboTrunk is not the seller and never holds the money. Buying works in one path. RoboTrunk's tools prepare a checkout at that store, then hand back a short-lived link. The person approves the total; once RoboTrunk has checked the store's total against it, the person is given the checkout link to tap in their own browser, or, if the person prefers and gives permission, their agent may open the link and finish there, and payment always happens on the store's own checkout page. RoboTrunk never takes the payment or sees a card. Where the rest of this site is: - /agent/story.md is what RoboTrunk is and how it works, in full. - /agent/tools.json is every tool, its arguments and its answers. - /agent/merchants is every store you can buy from through RoboTrunk. - /products/ucp is every store's indexed products. - /products/search is one search across every store, in plain words. - [What RoboTrunk is](/agent/story.md) - [Every tool, in your browser through WebMCP](/agent) - [The tools and how to call them](/agent/tools.json) - [The stores you can buy from](/agent/merchants) - [Every store's products](/products/ucp) - [Search every store at once](/products/search)