The Big History Project: Adapting BHP for Elementary Aged Kids. Threshold 2.0 – The Big Bang

In our homeschool we focus a great deal on science, not just because we all love science, but also because science topics often turn into philosophy and history discussions (which we also love) and they easily lead into reading and writing assignments. I find that if we start with science, we end up covering multiple topics and my kids remain enthusiastic and engaged throughout it all.

This is especially so with our core curriculum, the Big History Project. Funded by Bill Gates and offered to the world for free at, the Big History Project covers history from the moment of the big bang through modern times. For children (and adults) who like asking big questions and having a very sequential understanding of where life / Earth / the universe began, this is a one-stop program!

screen shot 2019-01-27 at 10.30.20 am

Each threshold, or point in time when a major event changed the course of the universe forever, is recognized in the Big History Project with its own unit. The first important threshold, Threshold 1 in Unit 2.0, is the big bang.

screen shot 2019-01-27 at 10.29.53 am

Since the Big History Project was intended for high school students, I have adapted it to my kids’ age levels (ages 10.5, 6.5 and almost 3). These adaptations are what I would like to share with you all, in case you find yourself as captivated as I am by the program. A disclaimer before we begin though: I don’t dumb down the topics for my young kids. Whenever I can, I use analogies that are relevant to their personal experiences in order to explain things that are pretty abstract, using familiar ideas to help us delve deeply into new concepts rather than simplifying the material. I stick closely to the scientific ideas, vocabulary, articles and videos with adjustments for attention-span (I summarize articles rather than reading them, for example) and interest.

My focus is on elaborate discussions of the topics followed by age-appropriate art projects, reading and activities. When something is particularly fascinating, we happily follow it down a rabbit hole for as long as it holds interest, then we return to the main thread of the program.

I won’t go into the details of every section of the website –  there is a TON of material on there! – but instead I’ll list the section headings that I focus on in our homeschool and explain what I did to engage my elementary aged children with the topics.

2.0 The Big Bang


Everything starts here. My kids and I LOVE discussions / chats / brainstorms about captivating topics. In Unit 2.0, we began by discussing how scientists believe that the universe started in one huge, explosive event … and how it is impossible to know what came before the big bang. I used the analogy of a sneeze to explain how, out of no where, energy built up enough to send the building blocks of the universe flying out in all directions. (This is far from an accurate description, since the entire universe – including the very fabric of space-time, not just the objects that exist within it – began its rapid expansion and acceleration at this critical moment, but the sneeze analogy does garner some laughs …)

What caused the big bang? Like all thresholds in the Big History Project, conditions for change had to be just right. Temperature, pressure, and other environmental variables had to come together in just the right way to trigger significant, irreversible movement. These are called Goldilocks Conditions.

This is a natural point to invoke children’s literature in your discussion: my toddler was thrilled to discuss Goldilocks and her highly-tuned, if somewhat picky, preferences (too hot, too cold, too hard, too soft …). It is easy for kids to understand how the universe itself had to be “just right” before any tremendous changes could happen!

And while we can’t know the specifics of the Goldilocks Conditions that triggered the big bang (in other words, the conditions just microseconds before the big bang occurred), we can determine a lot about the conditions after the big bang … such as the temperature changes that caused subatomic particles to coalesce into nuclei once matter was distributed throughout space (forming the plasma soup, which we will discuss shortly).

But first, let’s talk about human limitations. This is a very important topic and it’s something my kids and I discuss frequently – in fact, we talk about it nearly every time we discuss these early Big History topics, since astrophysics ideas tend to push the boundaries of what our human minds can conceptualize.

Human Limitations

There is a set amount of information that humans can perceive. Our ears can detect sound in the range of 0 – 140 decibels. Our eyes can detect electromagnetic waves in the range of 390 – 700 nanometers. Our senses of touch, smell and taste are equally limited – we are “receivers” that are sensitive to very distinct types of information. We are inherently limited in what we can perceive in the world around us.

Therefore we must rely on technological equipment to detect information that falls outside of these ranges.

But what about information that not even our most sensitive equipment can detect? The important thing is to understand that information (whether it be in the form of electromagnetic waves, sound waves, or some other shape) exists in the universe that we cannot detect and directly know about. We very well might see the effects this information has on things we do understand (like dark matter exerting a gravitational pull on objects we can see and measure) but, due to human limitations, we cannot directly witness everything that is happening – and has happened – in our universe.

For now, the important idea is just to realize this. It will come up over and over as we discuss these big topics.

But back to the big bang.

2.0 – The Big Bang, Once Again

Once the big bang happened, all energy that “flew” out from its epicenter behaved in a curious way. It (1) expanded out from the source of the “bang” (which is intuitive), and (2) it accelerated out from its source (which is counter-intuitive).

Although it makes sense that all the “stuff” thrown outwards from the big bang would expand, at least initially, you would think that this expanding stuff would decelerate and eventually stop, right?

This is a great question to discuss with kids. Curiously, the universe doesn’t behave the way that we would expect it to given how things behave on Earth. Everything that “flew” outward from the big bang is still flying outward, 13.8 billion years later, and it is flying outward faster than ever rather than slowing down.

We will follow up on the concepts of expansion and acceleration when we discuss the early astronomers and their observations, but I do think this is a good time to chat with your kids (as I did) about two things: (1) friction. On Earth, friction plays a significant role in how objects behave. It helps slow things down, it allows us to move freely, and it serves as a basis for how we naturally want to interpret movement throughout the universe. And (2) the universe’s acceleration (rather than deceleration) is an example of how the way we interpret information on Earth can be very different than how we interpret information in outer space.

The Plasma Soup

After discussing these basic elements of the big bang, we naturally began discussing the moment immediately after the big bang. In much less than a microsecond after the big bang, a plasma soup formed – a huge expanse of gluons and quarks. These are the subatomic particles that ultimately fuse together to form protons and neutrons, and they were suddenly spreading out through the fabric of space-time.

When the Goldilocks Conditions were just right a few more microseconds later – when the temperature cooled enough to slow down the rapidly moving particles and allow them to close-in on each other – protons and neutrons began forming out of the plasma soup. This critical threshold ultimately led to the formation of atoms.

My kids love chemistry – I’ve yet to meet a kid who doesn’t actually – and they use their organic chemistry molecule kit very much like legos. I was wishing we had a kit that was composed of neutron and protons at this point (or even quarks!) but since I didn’t have one, we pulled out the o-chem kit and played around for awhile, trying to visualize the first nuclei.

screen shot 2019-01-27 at 10.54.37 am

And now for our activities (if you end up following this program yourself, or if you have any big bang related activities that you have done, please share! I am always looking for new ideas and back-tracking to topics we’ve previously covered in order to go more in depth).

Big Bang Activities


Our first activity was to paint our interpretation of both the big bang and the plasma soup – myself included. (I try to follow up our discussions with art projects as much as possible … it seems like a natural extension of opening up our minds to new concepts). My kids really enjoy when I join in on the projects … as do I, so long as my five-month old is content and my hands are free.

Here are examples of our work:



We watched a number of videos from the BHP website, including Threshold 1: The Big Bang, and A Big History of Everything – H2. It is easy to access these videos and more after making a free account on the BHP website – they are listed under Unit 2.0. And while some of the language is advanced for my young students, they learned a ton from these short, informative, engaging videos. I am a strong proponent to exposure … I feel that by viewing scientists discussing these larger than life topics my kids gain a great deal, whether or not it be a perfect understanding of the topic.

Hands-On Activities

Our final hands-on activity was one we have repeated a number of times since then: drawing dots on a deflated balloon and then blowing it up. This is the simplest way to convey the idea that the universe is composed of the fabric of space-time (analogous to the surface of a balloon) and that all objects on this fabric (the dots) are moving away from every other dot as the universe continuously expands.

What We Got Out of Unit 2.0

For me, the important take-aways from Unit 2.0 were for my kids to understand that there are limits to human perception; that counter-intuitive events happen in our universe and we must stretch our minds to think about them; that scientists currently believe that our universe originated in an event called the Big Bang; and that subatomic particles began “sticking together” to form atoms in the plasma soup.

My next post will be about Unit 2.1 – How Did Our Understanding of the Universe Change? and the astronomers who stretched their minds to painstakingly piece together (over centuries and centuries) an accurate understanding of how the cosmos work. We had a great time exploring their ideas and coming up with our own in the process!




  1. Thanks for this inspiring post, Lindsey! We’ve been exploring the Troposphere and are now expanding outward to talk about space-time and gravity, which has naturally led to curiosity about the origin of the Universe. We’ve been watching some related NOVA videos, and I’ve been brainstorming ideas to convey and explore these concepts via hands-on activities, so I’m definitely going to try some of your suggestions. Amazing stuff, and so fun to delve into it further with young eager minds! I’m headed over to check out the BHP site now – it sounds like a great resource.

    On a related note, If you haven’t already seen it, Beyond a Year in Space is a PBS program that goes into fascinating detail about the challenges of long-term missions in space, and how those unseen forces affect the human body in different ways as we move away from planetary bodies and out into the undulating fabric of space-time.

  2. Thanks so much for this info and feedback, Randi! I will definitely check out the PBS program … that sounds spot-on in terms of what I want to teach my kids. It’s all so fascinating. If you find anymore great resources, please let me know. I love that you guys are studying this right now as well 🙂

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s